MediaWiki REL1_40
Wikimedia\Rdbms\Database Class Reference

Relational database abstraction object. More...

Inherits Wikimedia\Rdbms\IDatabase, Wikimedia\Rdbms\IMaintainableDatabase, and LoggerAwareInterface.

Inherited by Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Collaboration diagram for Wikimedia\Rdbms\Database:

Public Member Functions

 __clone ()
 Make sure that copies do not share the same client binding handle.
 
 __construct (array $params)
 
 __destruct ()
 Run a few simple checks and close dangling connections.
 
 __sleep ()
 Called by serialize.
 
 __toString ()
 Get a debugging string that mentions the database type, the ID of this instance, and the ID of any underlying connection resource or driver object if one is present.
 
 addIdentifierQuotes ( $s)
 Escape a SQL identifier (e.g.
 
 addQuotes ( $s)
 Escape and quote a raw value string for use in a SQL query.
Parameters
string | int | float | null | bool | Blob$s
Returns
string

 
 affectedRows ()
 Get the number of rows affected by the last attempted query statement.
 
 anyChar ()
 Returns a token for buildLike() that denotes a '_' to be used in a LIKE query.
 
 anyString ()
 Returns a token for buildLike() that denotes a '' to be used in a LIKE query.
 
 begin ( $fname=__METHOD__, $mode=self::TRANSACTION_EXPLICIT)
 Begin a transaction.
 
 bitAnd ( $fieldLeft, $fieldRight)
 
 bitNot ( $field)
 
 bitOr ( $fieldLeft, $fieldRight)
 
 buildComparison (string $op, array $conds)
 Build a condition comparing multiple values, for use with indexes that cover multiple fields, common when e.g.
 
 buildConcat ( $stringList)
 Build a concatenation list to feed into a SQL query.
 
 buildExcludedValue ( $column)
 Build a reference to a column value from the conflicting proposed upsert() row.
 
 buildGreatest ( $fields, $values)
 Build a GREATEST function statement comparing columns/values.
 
 buildGroupConcatField ( $delim, $table, $field, $conds='', $join_conds=[])
 Build a GROUP_CONCAT or equivalent statement for a query.
 
 buildIntegerCast ( $field)
 
 buildLeast ( $fields, $values)
 Build a LEAST function statement comparing columns/values.
 
 buildLike ( $param,... $params)
 LIKE statement wrapper.
 
 buildSelectSubquery ( $table, $vars, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
 Equivalent to IDatabase::selectSQLText() except wraps the result in Subquery.
 
 buildStringCast ( $field)
 
 buildSubstring ( $input, $startPosition, $length=null)
 
 cancelAtomic ( $fname=__METHOD__, AtomicSectionIdentifier $sectionId=null)
 Cancel an atomic section of SQL statements.
 
 clearFlag ( $flag, $remember=self::REMEMBER_NOTHING)
 Clear a flag for this connection.
 
 close ( $fname=__METHOD__)
 Close the database connection.
 
 commit ( $fname=__METHOD__, $flush=self::FLUSHING_ONE)
 Commits a transaction previously started using begin()
 
 conditional ( $cond, $caseTrueExpression, $caseFalseExpression)
 Returns an SQL expression for a simple conditional.
 
 connectionErrorLogger ( $errno, $errstr)
 Error handler for logging errors during database connection.
 
 databasesAreIndependent ()
 Returns true if DBs are assumed to be on potentially different servers.In systems like mysql/mariadb, different databases can easily be referenced on a single connection merely by name, even in a single query via JOIN. On the other hand, Postgres treats databases as logically separate, with different database users, requiring special mechanisms like postgres_fdw to "mount" foreign DBs. This is true even among DBs on the same server. Changing the selected database via selectDomain() requires a new connection.
Returns
bool
Since
1.29

 
 dbSchema ( $schema=null)
 Get/set the db schema.
 
 decodeBlob ( $b)
 Some DBMSs return a special placeholder object representing blob fields in result objects.Pass the object through this function to return the original string.
Parameters
string | Blob$b
Returns
string
Exceptions
DBError

 
 decodeExpiry ( $expiry, $format=TS_MW)
 Decode an expiry time into a DBMS independent format.
 
 delete ( $table, $conds, $fname=__METHOD__)
 Delete all rows in a table that match a condition.
 
 deleteJoin ( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname=__METHOD__)
 Delete all rows in a table that match a condition which includes a join.For safety, an empty $conds will not delete everything. If you want to delete all rows where the join condition matches, set $conds=IDatabase::ALL_ROWS.DO NOT put the join condition in $conds.This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.
Parameters
string$delTableThe table to delete from.
string$joinTableThe reference table used by the join (not modified).
string$delVarThe variable to join on, in the first table.
string$joinVarThe variable to join on, in the second table.
array | string$condsCondition array of field names mapped to variables, ANDed together in the WHERE clause
string$fnameCalling function name (use METHOD) for logs/profiling
Exceptions
DBErrorIf an error occurs, {
See also
query}

 
 doAtomicSection ( $fname, callable $callback, $cancelable=self::ATOMIC_NOT_CANCELABLE)
 Perform an atomic section of reversible SQL statements from a callback.
 
 dropTable ( $table, $fname=__METHOD__)
 Delete a table.
 
 duplicateTableStructure ( $oldName, $newName, $temporary=false, $fname=__METHOD__)
 Creates a new table with structure copied from existing table.Note that unlike most database abstraction functions, this function does not automatically append database prefix, because it works at a lower abstraction level. The table names passed to this function shall not be quoted (this function calls addIdentifierQuotes() when needed).
Parameters
string$oldNameName of table whose structure should be copied
string$newNameName of table to be created
bool$temporaryWhether the new table should be temporary
string$fnameCalling function name
Returns
bool True if operation was successful
Exceptions
RuntimeException

 
 encodeBlob ( $b)
 Some DBMSs have a special format for inserting into blob fields, they don't allow simple quoted strings to be inserted.To insert into such a field, pass the data through this function before passing it to IDatabase::insert().
Parameters
string$b
Returns
string|Blob
Exceptions
DBError

 
 encodeExpiry ( $expiry)
 Encode an expiry time into the DBMS dependent format.
 
 endAtomic ( $fname=__METHOD__)
 Ends an atomic section of SQL statements.
 
 estimateRowCount ( $tables, $var=' *', $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
 Estimate the number of rows in dataset.MySQL allows you to estimate the number of rows that would be returned by a SELECT query, using EXPLAIN SELECT. The estimate is provided using index cardinality statistics, and is notoriously inaccurate, especially when large numbers of rows have recently been added or deleted.For DBMSs that don't support fast result size estimation, this function will actually perform the SELECT COUNT(*).Takes the same arguments as IDatabase::select().New callers should use newSelectQueryBuilder with SelectQueryBuilder::estimateRowCount instead, which is more readable and less error-prone.
Parameters
string | string[]$tablesTable name(s)
string$varColumn for which NULL values are not counted [default "*"]
array | string$condsFilters on the table
string$fnameFunction name for profiling
array$optionsOptions for select
array | string$join_condsJoin conditions
Returns
int Row count
Exceptions
DBErrorIf an error occurs, {
See also
query}

 
 explicitTrxActive ()
 Check whether there is a transaction open at the specific request of a caller.
 
 factorConds ( $condsArray)
 Given an array of condition arrays representing an OR list of AND lists, for example:
 
 fieldExists ( $table, $field, $fname=__METHOD__)
 Determines whether a field exists in a table.
 
 flushSession ( $fname=__METHOD__, $flush=self::FLUSHING_ONE)
 Release important session-level state (named lock, table locks) as post-rollback cleanup.
 
 flushSnapshot ( $fname=__METHOD__, $flush=self::FLUSHING_ONE)
 Commit any transaction but error out if writes or callbacks are pending.
 
 getDBname ()
 Get the current database name; null if there isn't one.
 
 getDomainID ()
 Return the currently selected domain ID.
 
 getFlag ( $flag)
 Returns a boolean whether the flag $flag is set for this connection.
 
 getInfinity ()
 Find out when 'infinity' is.
 
 getLag ()
 Get the amount of replication lag for this database server.
 
 getLBInfo ( $name=null)
 Get properties passed down from the server info array of the load balancer.
 
 getPrimaryPos ()
 Get the position of this primary DB.
 
 getReplicaPos ()
 Get the replication position of this replica DB.
 
 getScopedLockAndFlush ( $lockKey, $fname, $timeout)
 Acquire a named lock, flush any transaction, and return an RAII style unlocker object.
 
 getServer ()
 Get the hostname or IP address of the server.
 
 getServerInfo ()
 Get a human-readable string describing the current software version.
 
 getServerName ()
 Get the readable name for the server.
 
 getSessionLagStatus ()
 Get the replica server lag when the current transaction started or a general lag estimate if not transaction is active.
 
 getTableAliases ()
 Return current table aliases.
 
 getTopologyBasedServerId ()
 Get a non-recycled ID that uniquely identifies this server within the replication topology.
 
 getTopologyRole ()
 Get the replication topology role of this server.
 
 getValueTypesForWithClause ( $table)
 
 implicitOrderby ()
 Returns true if this database does an implicit order by when the column has an index For example: SELECT page_title FROM page LIMIT 1.
 
 indexExists ( $table, $index, $fname=__METHOD__)
 Determines whether an index exists.
 
 indexInfo ( $table, $index, $fname=__METHOD__)
 Get information about an index into an object.
 
 indexUnique ( $table, $index, $fname=__METHOD__)
 Determines if a given index is unique.
Parameters
string$table
string$index
string$fnameCalling function name
Returns
bool

 
 initConnection ()
 Initialize the connection to the database over the wire (or to local files)
 
 insert ( $table, $rows, $fname=__METHOD__, $options=[])
 Insert row(s) into a table, in the provided order.
 
 insertSelect ( $destTable, $srcTable, $varMap, $conds, $fname=__METHOD__, $insertOptions=[], $selectOptions=[], $selectJoinConds=[])
 INSERT SELECT wrapper.
 
 isOpen ()
 
 isQuotedIdentifier ( $name)
 
 isReadOnly ()
 
 lastDoneWrites ()
 Get the last time the connection may have been used for a write query.
 
 lastQuery ()
 Get the last query that sent on account of IDatabase::query()
 
 limitResult ( $sql, $limit, $offset=false)
 Construct a LIMIT query with optional offset.
 
 listTables ( $prefix=null, $fname=__METHOD__)
 List all tables on the database.
Parameters
string | null$prefixOnly show tables with this prefix, e.g. mw_
string$fnameCalling function name
Exceptions
DBError
Returns
array

 
 listViews ( $prefix=null, $fname=__METHOD__)
 Lists all the VIEWs in the database.
Parameters
string | null$prefixOnly show VIEWs with this prefix, eg. unit_test_
string$fnameName of calling function
Exceptions
RuntimeException
Returns
array

 
 lock ( $lockName, $method, $timeout=5, $flags=0)
 Acquire a named lock.Named locks are not related to transactions
Parameters
string$lockNameName of lock to acquire
string$methodName of the calling method
int$timeoutAcquisition timeout in seconds (0 means non-blocking)
int$flagsBit field of IDatabase::LOCK_* constants
Returns
bool|float|null Success (bool); acquisition time (float/null) if LOCK_TIMESTAMP
Exceptions
DBErrorIf an error occurs, {
See also
query}

 
 lockForUpdate ( $table, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
 Lock all rows meeting the given conditions/options FOR UPDATE.
 
 lockIsFree ( $lockName, $method)
 Check to see if a named lock is not locked by any thread (non-blocking)
Parameters
string$lockNameName of lock to poll
string$methodName of method calling us
Returns
bool
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.20

 
 makeList (array $a, $mode=self::LIST_COMMA)
 Makes an encoded list of strings from an array.
 
 makeWhereFrom2d ( $data, $baseKey, $subKey)
 Build a partial where clause from a 2-d array such as used for LinkBatch.
 
 namedLocksEnqueue ()
 Check to see if a named lock used by lock() use blocking queues.
Returns
bool
Since
1.26

 
 newSelectQueryBuilder ()
 Get a SelectQueryBuilder bound to this connection.
 
 newUpdateQueryBuilder ()
 Get an UpdateQueryBuilder bound to this connection.
 
 nextSequenceValue ( $seqName)
 Deprecated method, calls should be removed.
 
 onAtomicSectionCancel (callable $callback, $fname=__METHOD__)
 Run a callback when the atomic section is cancelled.
 
 onTransactionCommitOrIdle (callable $callback, $fname=__METHOD__)
 Run a callback when the current transaction commits or now if there is none.
 
 onTransactionPreCommitOrIdle (callable $callback, $fname=__METHOD__)
 Run a callback before the current transaction commits or now if there is none.
 
 onTransactionResolution (callable $callback, $fname=__METHOD__)
 Run a callback when the current transaction commits or rolls back.
 
 pendingWriteAndCallbackCallers ()
 
 pendingWriteCallers ()
 Get the list of method names that did write queries for this transaction.
 
 pendingWriteQueryDuration ( $type=self::ESTIMATE_TOTAL)
 Get the time spend running write queries for this transaction.
 
 ping ()
 Ping the server and try to reconnect if it there is no connection.
 
 primaryPosWait (DBPrimaryPos $pos, $timeout)
 Wait for the replica server to catch up to a given primary server position.
 
 query ( $sql, $fname=__METHOD__, $flags=0)
 Run an SQL query statement and return the result.
 
 queryMulti (array $sqls, string $fname=__METHOD__, int $flags=0, ?string $summarySql=null)
 Run a batch of SQL query statements and return the results.
 
 replace ( $table, $uniqueKeys, $rows, $fname=__METHOD__)
 Insert row(s) into a table, in the provided order, while deleting conflicting rows.
 
 reportQueryError ( $error, $errno, $sql, $fname, $ignore=false)
 Report a query error.
 
 restoreFlags ( $state=self::RESTORE_PRIOR)
 Restore the flags to their prior state before the last setFlag/clearFlag call.
 
 rollback ( $fname=__METHOD__, $flush=self::FLUSHING_ONE)
 Rollback a transaction previously started using begin()
 
 runOnTransactionIdleCallbacks ( $trigger, array &$errors=[])
 Consume and run any "on transaction idle/resolution" callbacks.
 
 runOnTransactionPreCommitCallbacks ()
 
 runTransactionListenerCallbacks ( $trigger, array &$errors=[])
 Actually run any "transaction listener" callbacks.
 
 select ( $table, $vars, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
 Execute a SELECT query constructed using the various parameters provided.
 
 selectDomain ( $domain)
 Set the current domain (database, schema, and table prefix)
 
 selectField ( $table, $var, $cond='', $fname=__METHOD__, $options=[], $join_conds=[])
 A SELECT wrapper which returns a single field from a single result row.
 
 selectFieldValues ( $table, $var, $cond='', $fname=__METHOD__, $options=[], $join_conds=[])
 A SELECT wrapper which returns a list of single field values from result rows.
 
 selectRow ( $table, $vars, $conds, $fname=__METHOD__, $options=[], $join_conds=[])
 Wrapper to IDatabase::select() that only fetches one row (via LIMIT)
 
 selectRowCount ( $tables, $var=' *', $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
 Get the number of rows in dataset.
 
 selectSQLText ( $table, $vars, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
 Take the same arguments as IDatabase::select() and return the SQL it would use.
 
 serverIsReadOnly ()
 
Returns
bool Whether the DB server is marked as read-only server-side
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.28

 
 sessionLocksPending ()
 
 setFlag ( $flag, $remember=self::REMEMBER_NOTHING)
 Set a flag for this connection.
 
 setIndexAliases (array $aliases)
 Convert certain index names to alternative names before querying the DB.
 
 setLBInfo ( $nameOrArray, $value=null)
 Set the entire array or a particular key of the managing load balancer info array.
 
 setLogger (LoggerInterface $logger)
 Set the PSR-3 logger interface to use.
 
 setSchemaVars ( $vars)
 Set schema variables to be used when streaming commands from SQL files or stdin.
 
 setSessionOptions (array $options)
 Override database's default behavior.$options include: 'connTimeout' : Set the connection timeout value in seconds. May be useful for very long batch queries such as full-wiki dumps, where a single query reads out over hours or days.
Parameters
array$options
Returns
void
Exceptions
DBErrorIf an error occurs, {
See also
query}

 
 setTableAliases (array $aliases)
 Make certain table names use their own database, schema, and table prefix when passed into SQL queries pre-escaped and without a qualified database name.
 
 setTransactionListener ( $name, callable $callback=null)
 Run a callback after each time any transaction commits or rolls back.
 
 setTransactionManager (TransactionManager $transactionManager)
 
 setTrxEndCallbackSuppression ( $suppress)
 Whether to disable running of post-COMMIT/ROLLBACK callbacks.
 
 sourceFile ( $filename, callable $lineCallback=null, callable $resultCallback=null, $fname=false, callable $inputCallback=null)
 Read and execute SQL commands from a file.
 
 sourceStream ( $fp, callable $lineCallback=null, callable $resultCallback=null, $fname=__METHOD__, callable $inputCallback=null)
 Read and execute commands from an open file handle.
 
 startAtomic ( $fname=__METHOD__, $cancelable=self::ATOMIC_NOT_CANCELABLE)
 Begin an atomic section of SQL statements.
 
 streamStatementEnd (&$sql, &$newLine)
 Called by sourceStream() to check if we've reached a statement end.
 
 strencode ( $s)
 Wrapper for addslashes()
 
 strreplace ( $orig, $old, $new)
 Returns a SQL expression for simple string replacement (e.g.
 
 tableExists ( $table, $fname=__METHOD__)
 Query whether a given table exists.
 
 tableName ( $name, $format='quoted')
 Format a table name ready for use in constructing an SQL query.
 
 tableNames (... $tables)
 Fetch a number of table names into an associative array.
 
 tableNamesN (... $tables)
 Fetch a number of table names into a zero-indexed numerical array.
 
 tablePrefix ( $prefix=null)
 Get/set the table prefix.
 
 textFieldSize ( $table, $field)
 Returns the size of a text field, or -1 for "unlimited".
Parameters
string$table
string$field
Returns
int

 
 timestamp ( $ts=0)
 Convert a timestamp in one of the formats accepted by ConvertibleTimestamp to the format used for inserting into timestamp fields in this DBMS.
 
 timestampOrNull ( $ts=null)
 Convert a timestamp in one of the formats accepted by ConvertibleTimestamp to the format used for inserting into timestamp fields in this DBMS.
 
 truncate ( $tables, $fname=__METHOD__)
 Delete all data in a table(s) and reset any sequences owned by that table(s)
 
 trxLevel ()
 Gets the current transaction level.
 
 trxStatus ()
 
 trxTimestamp ()
 Get the UNIX timestamp of the time that the transaction was established.
 
 unionConditionPermutations ( $table, $vars, array $permute_conds, $extra_conds='', $fname=__METHOD__, $options=[], $join_conds=[])
 Construct a UNION query for permutations of conditions.
 
 unionQueries ( $sqls, $all)
 Construct a UNION query.
 
 unionSupportsOrderAndLimit ()
 Determine if the RDBMS supports ORDER BY and LIMIT for separate subqueries within UNION.
 
 unlock ( $lockName, $method)
 Release a lock.Named locks are not related to transactions
Parameters
string$lockNameName of lock to release
string$methodName of the calling method
Returns
bool Success
Exceptions
DBErrorIf an error occurs, {
See also
query}

 
 update ( $table, $set, $conds, $fname=__METHOD__, $options=[])
 Update all rows in a table that match a given condition.
 
 upsert ( $table, array $rows, $uniqueKeys, array $set, $fname=__METHOD__)
 Upsert row(s) into a table, in the provided order, while updating conflicting rows.
 
 wasConnectionLoss ()
 Determines if the last query error was due to a dropped connection.Note that during a connection loss, the prior transaction will have been lost
Returns
bool
Since
1.31

 
 wasDeadlock ()
 Determines if the last failure was due to a deadlock.Note that during a deadlock, the prior transaction will have been lost
Returns
bool

 
 wasErrorReissuable ()
 Determines if the last query error was due to something outside of the query itself.
 
 wasLockTimeout ()
 Determines if the last failure was due to a lock timeout.Note that during a lock wait timeout, the prior transaction will have been lost
Returns
bool

 
 wasReadOnlyError ()
 Determines if the last failure was due to the database being read-only.
Returns
bool

 
 writesOrCallbacksPending ()
 Whether there is a transaction open with either possible write queries or unresolved pre-commit/commit/resolution callbacks pending.
 
 writesPending ()
 
- Public Member Functions inherited from Wikimedia\Rdbms\IDatabase
 insertId ()
 Get the inserted value of an auto-increment row.
 
- Public Member Functions inherited from Wikimedia\Rdbms\IReadableDatabase
 getServerVersion ()
 A string describing the current software version, like from mysql_get_server_info()
 
 getSoftwareLink ()
 Returns a wikitext style link to the DB's website (e.g.
 
 getType ()
 Get the RDBMS type of the server (e.g.
 
 lastErrno ()
 Get the RDBMS-specific error code from the last attempted query statement.
 
 lastError ()
 Get the RDBMS-specific error description from the last attempted query statement.
 
- Public Member Functions inherited from Wikimedia\Rdbms\Platform\ISQLPlatform
 buildSubString ( $input, $startPosition, $length=null)
 Build a SUBSTRING function.
 
- Public Member Functions inherited from Wikimedia\Rdbms\IMaintainableDatabase
 fieldInfo ( $table, $field)
 Get information about a field Returns false if the field doesn't exist.
 

Static Public Member Functions

static factory ( $type, $params=[], $connect=self::NEW_CONNECTED)
 Construct a Database subclass instance given a database type and parameters.
 
static getAttributes ()
 
static getCacheSetOptions (?IDatabase ... $dbs)
 Merge the result of getSessionLagStatus() for several DBs using the most pessimistic values to estimate the lag of any data derived from them in combination.
 

Protected Member Functions

 assertHasConnectionHandle ()
 Make sure there is an open connection handle (alive or not)
 
 assertIsWritablePrimary ()
 Make sure that this server is not marked as a replica nor read-only.
 
 closeConnection ()
 Closes underlying database connection.
 
 commenceCriticalSection (string $fname)
 Demark the start of a critical section of session/transaction state changes.
 
 completeCriticalSection (string $fname, ?CriticalSectionScope $csm, Throwable $trxError=null)
 Demark the completion of a critical section of session/transaction state changes.
 
 doBegin ( $fname)
 Issues the BEGIN command to the database server.
 
 doCommit ( $fname)
 Issues the COMMIT command to the database server.
 
 doFlushSession ( $fname)
 Reset the server-side session state for named locks and table locks.
 
 doHandleSessionLossPreconnect ()
 Reset any additional subclass trx* and session* fields.
 
 doInitConnection ()
 Actually connect to the database over the wire (or to local files)
 
 doInsertSelectGeneric ( $destTable, $srcTable, array $varMap, $conds, $fname, array $insertOptions, array $selectOptions, $selectJoinConds)
 Implementation of insertSelect() based on select() and insert()
 
 doInsertSelectNative ( $destTable, $srcTable, array $varMap, $conds, $fname, array $insertOptions, array $selectOptions, $selectJoinConds)
 Native server-side implementation of insertSelect() for situations where we don't want to select everything into memory.
 
 doLock (string $lockName, string $method, int $timeout)
 
 doLockIsFree (string $lockName, string $method)
 
 doMultiStatementQuery (array $sqls)
 Execute a batch of query statements, aborting remaining statements if one fails.
 
 doReplace ( $table, array $identityKey, array $rows, $fname)
 
 doSelectDomain (DatabaseDomain $domain)
 
 doSingleStatementQuery (string $sql)
 Run a query and return a QueryStatus instance with the query result information.
 
 doTruncate (array $tables, $fname)
 
 doUnlock (string $lockName, string $method)
 
 doUpsert (string $table, array $rows, array $identityKey, array $set, string $fname)
 Perform an UPSERT query.
 
 executeQuery ( $sqls, $fname, $flags, $summarySql)
 Execute a set of queries without enforcing public (non-Database) caller restrictions.
 
 fetchAffectedRowCount ()
 
 getBindingHandle ()
 Get the underlying binding connection handle.
 
 getLastPHPError ()
 
 getLogContext (array $extras=[])
 Create a log context to pass to PSR-3 logger functions.
 
 getReadOnlyReason ()
 
 getTempTableWrites ( $sql, $pseudoPermanent)
 
 getTransactionRoundId ()
 
 indexName ( $index)
 
 installErrorHandler ()
 Set a custom error handler for logging errors during database connection.
 
 isConnectionError ( $errno)
 Do not use this method outside of Database/DBError classes.
 
 isInsertSelectSafe (array $insertOptions, array $selectOptions)
 
 isKnownStatementRollbackError ( $errno)
 
 isPristineTemporaryTable ( $table)
 Check if the table is both a TEMPORARY table and has not yet received CRUD operations.
 
 isQueryTimeoutError ( $errno)
 Checks whether the cause of the error is detected to be a timeout.
 
 newExceptionAfterConnectError ( $error)
 
 open ( $server, $user, $password, $db, $schema, $tablePrefix)
 Open a new connection to the database (closing any existing one)
 
 registerTempWrites ( $ret, array $changes)
 
 replaceLostConnection ( $lastErrno, $fname)
 Close any existing (dead) database connection and open a new connection.
 
 restoreErrorHandler ()
 Restore the previous error handler and return the last PHP error for this DB.
 

Protected Attributes

int null $affectedRowCount
 Affected row count for the last query statement.
 
string $agent
 Agent name for query profiling.
 
bool $cliMode
 Whether this PHP instance is for a CLI script.
 
object resource null $conn
 Database connection.
 
array< string, mixed > $connectionParams
 Connection parameters used by initConnection() and open()
 
string[] int[] float[] $connectionVariables
 SQL variables values to use for all new connections.
 
int null $connectTimeout
 Maximum seconds to wait on connection attempts.
 
CriticalSectionProvider null $csProvider
 
DatabaseDomain $currentDomain
 
string false $delimiter = ';'
 Current SQL query delimiter.
 
callable $deprecationLogger
 Deprecation logging callback.
 
callable $errorLogger
 Error logging callback.
 
DatabaseFlags $flagsHolder
 
string $lastConnectError = ''
 Last error during connection; empty string if none.
 
array $lbInfo = []
 Current LoadBalancer tracking information.
 
LoggerInterface $logger
 
int $nonNativeInsertSelectBatchSize
 Row batch size to use for emulated INSERT SELECT queries.
 
SQLPlatform $platform
 
callable null $profiler
 
int null $receiveTimeout
 Maximum seconds to wait on receiving query results.
 
ReplicationReporter $replicationReporter
 
string null $serverName
 Readable name or host/IP of the database server.
 
array< string, array > $sessionNamedLocks = []
 Map of (name => (UNIX time,trx ID)) for current lock() mutexes.
 
array< string, array > $sessionTempTables = []
 Map of (name => (type,pristine,trx ID)) for current temp tables.
 
BagOStuff $srvCache
 APC cache.
 
bool $ssl
 Whether to use SSL connections.
 
const CONN_HOST = 'host'
 Hostname or IP address to use on all connections.
 
const CONN_INITIAL_DB = 'dbname'
 Database name to use on initial connection.
 
const CONN_INITIAL_SCHEMA = 'schema'
 Schema name to use on initial connection.
 
const CONN_INITIAL_TABLE_PREFIX = 'tablePrefix'
 Table prefix to use on initial connection.
 
const CONN_PASSWORD = 'password'
 Database server password to use on all connections.
 
const CONN_USER = 'user'
 Database server username to use on all connections.
 
const DROPPED_CONN_BLAME_THRESHOLD_SEC = 3.0
 Assume that queries taking this long to yield connection loss errors are at fault.
 
const ERR_ABORT_QUERY = 2
 Abort query (no retries) due to a statement rollback (session/transaction intact)
 
const ERR_ABORT_SESSION = 8
 Abort and reset session due to server-side session-level state loss (locks, temp tables)
 
const ERR_ABORT_TRX = 4
 Abort any current transaction, by rolling it back, due to an error during the query.
 
const ERR_NONE = 0
 No errors occurred during the query.
 
const ERR_RETRY_QUERY = 1
 Retry query due to a connection loss detected while sending the query (session intact)
 

Additional Inherited Members

- Public Attributes inherited from Wikimedia\Rdbms\IDatabase
const LOCK_TIMESTAMP = 1
 Flag to return the lock acquisition timestamp (null if not acquired)
 
- Public Attributes inherited from Wikimedia\Rdbms\Platform\ISQLPlatform
const QUERY_PSEUDO_PERMANENT = 2
 Track a TEMPORARY table CREATE as if it was for a permanent table (for testing)
 

Detailed Description

Relational database abstraction object.

Stability: stable
to extend
Since
1.28

Definition at line 45 of file Database.php.

Constructor & Destructor Documentation

◆ __construct()

Wikimedia\Rdbms\Database::__construct ( array $params)
Note
exceptions for missing libraries/drivers should be thrown in initConnection()
Stability: stable
to call
Parameters
array$paramsParameters passed from Database::factory()

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 189 of file Database.php.

◆ __destruct()

Wikimedia\Rdbms\Database::__destruct ( )

Run a few simple checks and close dangling connections.

Definition at line 3517 of file Database.php.

Member Function Documentation

◆ __clone()

Wikimedia\Rdbms\Database::__clone ( )

Make sure that copies do not share the same client binding handle.

Exceptions
DBConnectionError

Definition at line 3477 of file Database.php.

◆ __sleep()

Wikimedia\Rdbms\Database::__sleep ( )

Called by serialize.

Throw an exception when DB connection is serialized. This causes problems on some database engines because the connection is not restored on unserialize.

Returns
never

Definition at line 3509 of file Database.php.

◆ __toString()

Wikimedia\Rdbms\Database::__toString ( )

Get a debugging string that mentions the database type, the ID of this instance, and the ID of any underlying connection resource or driver object if one is present.

Returns
string "<db type> object #<X>" or "<db type> object #<X> (resource/handle id #<Y>)"
Since
1.34

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 3452 of file Database.php.

◆ addIdentifierQuotes()

Wikimedia\Rdbms\Database::addIdentifierQuotes ( $s)

Escape a SQL identifier (e.g.

table, column, database) for use in a SQL query

Depending on the database this will either be backticks or "double quotes"

Parameters
string$s
Returns
string
Since
1.33

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3699 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\doSelectDomain(), and Wikimedia\Rdbms\DatabaseMysqlBase\duplicateTableStructure().

◆ addQuotes()

Wikimedia\Rdbms\Database::addQuotes ( $s)

Escape and quote a raw value string for use in a SQL query.

Parameters
string | int | float | null | bool | Blob$s
Returns
string

Stability: stable
to override

Implements Wikimedia\Rdbms\Database\DbQuoter.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 1817 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\doFlushSession(), and Wikimedia\Rdbms\DatabaseMysqlBase\open().

◆ affectedRows()

Wikimedia\Rdbms\Database::affectedRows ( )

Get the number of rows affected by the last attempted query statement.

Similar to https://www.php.net/mysql_affected_rows but includes rows matched but not changed (ie. an UPDATE which sets all fields to the same value they already have). To get the old mysql_affected_rows behavior, include non-equality of the fields in WHERE.

Returns
int

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2853 of file Database.php.

◆ anyChar()

Wikimedia\Rdbms\Database::anyChar ( )

Returns a token for buildLike() that denotes a '_' to be used in a LIKE query.

Returns
LikeMatch

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3711 of file Database.php.

◆ anyString()

Wikimedia\Rdbms\Database::anyString ( )

Returns a token for buildLike() that denotes a '' to be used in a LIKE query.

Returns
LikeMatch

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3715 of file Database.php.

◆ assertHasConnectionHandle()

Wikimedia\Rdbms\Database::assertHasConnectionHandle ( )
finalprotected

Make sure there is an open connection handle (alive or not)

This guards against fatal errors to the binding handle not being defined in cases where open() was never called or close() was already called.

Exceptions
DBUnexpectedError

Definition at line 641 of file Database.php.

◆ assertIsWritablePrimary()

Wikimedia\Rdbms\Database::assertIsWritablePrimary ( )
protected

Make sure that this server is not marked as a replica nor read-only.

Exceptions
DBReadOnlyError
Since
1.37

Definition at line 653 of file Database.php.

References $source.

◆ begin()

Wikimedia\Rdbms\Database::begin ( $fname = __METHOD__,
$mode = self::TRANSACTION_EXPLICIT )
final

Begin a transaction.

Only call this from code with outer transaction scope. See https://www.mediawiki.org/wiki/Database_transactions for details. Nesting of transactions is not supported.

Note that when the DBO_TRX flag is set (which is usually the case for web requests, but not for maintenance scripts), any previous database query will have started a transaction automatically.

Nesting of transactions is not supported. Attempts to nest transactions will cause a warning, unless the current transaction was started automatically because of the DBO_TRX flag.

Parameters
string$fnameCalling function name
string$modeA situationally valid IDatabase::TRANSACTION_* constant [optional]
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2625 of file Database.php.

◆ bitAnd()

Wikimedia\Rdbms\Database::bitAnd ( $fieldLeft,
$fieldRight )
Parameters
string | int$fieldLeft
string | int$fieldRight
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3651 of file Database.php.

◆ bitNot()

Wikimedia\Rdbms\Database::bitNot ( $field)
Parameters
string | int$field
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3647 of file Database.php.

◆ bitOr()

Wikimedia\Rdbms\Database::bitOr ( $fieldLeft,
$fieldRight )
Parameters
string | int$fieldLeft
string | int$fieldRight
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3655 of file Database.php.

◆ buildComparison()

Wikimedia\Rdbms\Database::buildComparison ( string $op,
array $conds )

Build a condition comparing multiple values, for use with indexes that cover multiple fields, common when e.g.

paging through results or doing batch operations.

For example, you might be displaying a list of people ordered alphabetically by their last and first name, split across multiple pages. The first page of the results ended at Jane Doe. When building the query for the next page, you would use:

$queryBuilder->where( $db->buildComparison( '>', [ 'last' => 'Doe', 'first' => 'Jane' ] ) );

This will return people whose last name follows Doe, or whose last name is Doe and first name follows Jane.

Note that the order of keys in the associative array $conds is significant, and must match the order of fields used by the index.

You might also use it to generate a simple comparison without writing raw SQL:

$db->buildComparison( '<=', [ 'key' => $val ] )
// equivalent to:
'key <= ' . $db->addQuotes( $val )
Parameters
string$opComparison operator, one of '>', '>=', '<', '<='
array$condsMap of field names to their values to use in the comparison
Returns
string SQL code

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3631 of file Database.php.

◆ buildConcat()

Wikimedia\Rdbms\Database::buildConcat ( $stringList)

Build a concatenation list to feed into a SQL query.

Parameters
string[]$stringListRaw SQL expression list; caller is responsible for escaping
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3659 of file Database.php.

◆ buildExcludedValue()

Wikimedia\Rdbms\Database::buildExcludedValue ( $column)

Build a reference to a column value from the conflicting proposed upsert() row.

The reference comes in the form of an alias, function, or parenthesized SQL expression. It can be used in upsert() SET expressions to handle the merging of column values between each conflicting pair of existing and proposed rows. Such proposed rows are said to have been "excluded" from insertion in favor of updating the existing row.

This is useful for multi-row upserts() since the proposed values cannot just be included as literals in the SET expressions.

See also
IDatabase::upsert()
Parameters
string$columnColumn name
Returns
string SQL expression returning a scalar
Since
1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3804 of file Database.php.

◆ buildGreatest()

Wikimedia\Rdbms\Database::buildGreatest ( $fields,
$values )

Build a GREATEST function statement comparing columns/values.

Integer and float values in $values will not be quoted

If $fields is an array, then each value with a string key is treated as an expression (which must be manually quoted); such string keys do not appear in the SQL and are only descriptive aliases.

Parameters
string | string[]$fieldsName(s) of column(s) with values to compare
string | int | float | string[] | int[] | float[]$valuesValues to compare
Returns
mixed
Since
1.35 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3663 of file Database.php.

◆ buildGroupConcatField()

Wikimedia\Rdbms\Database::buildGroupConcatField ( $delim,
$table,
$field,
$conds = '',
$join_conds = [] )

Build a GROUP_CONCAT or equivalent statement for a query.

This is useful for combining a field for several rows into a single string. NULL values will not appear in the output, duplicated values will appear, and the resulting delimiter-separated values have no defined sort order. Code using the results may need to use the PHP unique() or sort() methods.

Parameters
string$delimGlue to bind the results together
string | array$tableTable name
string$fieldField name
string | array$condsConditions
string | array$join_condsJoin conditions
Returns
string SQL text
Since
1.23

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3791 of file Database.php.

◆ buildIntegerCast()

Wikimedia\Rdbms\Database::buildIntegerCast ( $field)
Parameters
string$fieldField or column to cast
Returns
string
Since
1.31 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3679 of file Database.php.

◆ buildLeast()

Wikimedia\Rdbms\Database::buildLeast ( $fields,
$values )

Build a LEAST function statement comparing columns/values.

Integer and float values in $values will not be quoted

If $fields is an array, then each value with a string key is treated as an expression (which must be manually quoted); such string keys do not appear in the SQL and are only descriptive aliases.

Parameters
string | string[]$fieldsName(s) of column(s) with values to compare
string | int | float | string[] | int[] | float[]$valuesValues to compare
Returns
mixed
Since
1.35 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3667 of file Database.php.

◆ buildLike()

Wikimedia\Rdbms\Database::buildLike ( $param,
$params )

LIKE statement wrapper.

This takes a variable-length argument list with parts of pattern to match containing either string literals that will be escaped or tokens returned by anyChar() or anyString(). Alternatively, the function could be provided with an array of aforementioned parameters.

Example: $dbr->buildLike( 'My_page_title/', $dbr->anyString() ) returns a LIKE clause that searches for subpages of 'My page title'. Alternatively: $pattern = [ 'My_page_title/', $dbr->anyString() ]; $query .= $dbr->buildLike( $pattern );

Since
1.16 in IDatabase, moved to ISQLPlatform in 1.39
Parameters
array[] | string | LikeMatch$param
string|LikeMatch...$params
Returns
string Fully built LIKE statement

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3707 of file Database.php.

◆ buildSelectSubquery()

Wikimedia\Rdbms\Database::buildSelectSubquery ( $table,
$vars,
$conds = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Equivalent to IDatabase::selectSQLText() except wraps the result in Subquery.

See also
IDatabase::selectSQLText()
Parameters
string | array$tableTable name
string | array$varsField names
string | array$condsConditions
string$fnameCaller function name
string | array$optionsQuery options
string | array$join_condsJoin conditions
Returns
Subquery
Since
1.31

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3797 of file Database.php.

◆ buildStringCast()

Wikimedia\Rdbms\Database::buildStringCast ( $field)
Parameters
string$fieldField or column to cast
Returns
string
Since
1.28 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3675 of file Database.php.

◆ buildSubstring()

Wikimedia\Rdbms\Database::buildSubstring ( $input,
$startPosition,
$length = null )

Definition at line 3671 of file Database.php.

◆ cancelAtomic()

Wikimedia\Rdbms\Database::cancelAtomic ( $fname = __METHOD__,
AtomicSectionIdentifier $sectionId = null )
final

Cancel an atomic section of SQL statements.

This will roll back only the statements executed since the start of the most recent atomic section, and close that section. If a transaction was open before the corresponding startAtomic() call, any statements before that call are not rolled back and the transaction remains open. If the corresponding startAtomic() implicitly started a transaction, that transaction is rolled back.

Note
callers must use additional measures for situations involving two or more (peer) transactions (e.g. updating two database servers at once). The transaction and savepoint logic of startAtomic() are bound to specific IDatabase instances.

Note that a call to IDatabase::rollback() will also roll back any open atomic sections.

Note
As an optimization to save rountrips, this method may only be called when startAtomic() was called with the ATOMIC_CANCELABLE flag.
Since
1.31
See also
IDatabase::startAtomic
Parameters
string$fname
AtomicSectionIdentifier | null$sectionIdSection ID from startAtomic(); passing this enables cancellation of unclosed nested sections [optional]
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2532 of file Database.php.

◆ clearFlag()

Wikimedia\Rdbms\Database::clearFlag ( $flag,
$remember = self::REMEMBER_NOTHING )

Clear a flag for this connection.

Parameters
int$flagOne of (IDatabase::DBO_DEBUG, IDatabase::DBO_TRX)
string$rememberIDatabase::REMEMBER_* constant [default: REMEMBER_NOTHING]

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 3545 of file Database.php.

◆ close()

Wikimedia\Rdbms\Database::close ( $fname = __METHOD__)
final

Close the database connection.

This should only be called after any transactions have been resolved, aside from read-only automatic transactions (assuming no callbacks are registered). If a transaction is still open anyway, it will be rolled back.

Access: internal
Only for use by LoadBalancer
Parameters
string$fnameCaller name
Returns
bool Success
Exceptions
DBError

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 586 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\open(), Wikimedia\Rdbms\DatabasePostgres\open(), and Wikimedia\Rdbms\DatabaseSqlite\open().

◆ closeConnection()

Wikimedia\Rdbms\Database::closeConnection ( )
abstractprotected

Closes underlying database connection.

Returns
bool Whether connection was closed successfully
Since
1.20

Reimplemented in Wikimedia\Rdbms\DatabaseMysqli, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

◆ commenceCriticalSection()

Wikimedia\Rdbms\Database::commenceCriticalSection ( string $fname)
protected

Demark the start of a critical section of session/transaction state changes.

Use this to disable potentially DB handles due to corruption from highly unexpected exceptions (e.g. from zend timers or coding errors) preempting execution of methods.

Callers must demark completion of the critical section with completeCriticalSection(). Callers should handle DBError exceptions that do not cause object state corruption by catching them, calling completeCriticalSection(), and then rethrowing them.

$cs = $this->commenceCriticalSection( __METHOD__ );
try {
//...send a query that changes the session/transaction state...
} catch ( DBError $e ) {
$this->completeCriticalSection( __METHOD__, $cs );
throw $expectedException;
}
try {
//...send another query that changes the session/transaction state...
} catch ( DBError $trxError ) {
// Require ROLLBACK before allowing any other queries from outside callers
$this->completeCriticalSection( __METHOD__, $cs, $trxError );
throw $expectedException;
}
// ...update session state fields of $this...
$this->completeCriticalSection( __METHOD__, $cs );
Database error base class.
Definition DBError.php:31
See also
Database::completeCriticalSection()
Since
1.36
Parameters
string$fnameCaller name
Returns
CriticalSectionScope|null RAII-style monitor (topmost sections only)
Exceptions
DBUnexpectedErrorIf an unresolved critical section error already exists

Definition at line 3386 of file Database.php.

◆ commit()

Wikimedia\Rdbms\Database::commit ( $fname = __METHOD__,
$flush = self::FLUSHING_ONE )
final

Commits a transaction previously started using begin()

If no transaction is in progress, a warning is issued.

Only call this from code with outer transaction scope. See https://www.mediawiki.org/wiki/Database_transactions for details. Nesting of transactions is not supported.

Parameters
string$fname
string$flushFlush flag, set to situationally valid IDatabase::FLUSHING_* constant to disable warnings about explicitly committing implicit transactions, or calling commit when no transaction is in progress. This will trigger an exception if there is an ongoing explicit transaction. Only set the flush flag if you are sure that these warnings are not applicable, and no explicit transactions are open.
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2669 of file Database.php.

◆ completeCriticalSection()

Wikimedia\Rdbms\Database::completeCriticalSection ( string $fname,
?CriticalSectionScope $csm,
Throwable $trxError = null )
protected

Demark the completion of a critical section of session/transaction state changes.

See also
Database::commenceCriticalSection()
Since
1.36
Parameters
string$fnameCaller name
CriticalSectionScope | null$csmRAII-style monitor (topmost sections only)
Throwable | null$trxErrorError that requires setting STATUS_TRX_ERROR (if any)

Definition at line 3429 of file Database.php.

◆ conditional()

Wikimedia\Rdbms\Database::conditional ( $cond,
$caseTrueExpression,
$caseFalseExpression )

Returns an SQL expression for a simple conditional.

This doesn't need to be overridden unless CASE isn't supported in the RDBMS.

Parameters
string | array$condSQL condition expression (yields a boolean)
string$caseTrueExpressionSQL expression to return when the condition is true
string$caseFalseExpressionSQL expression to return when the condition is false
Returns
string SQL fragment

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3751 of file Database.php.

◆ connectionErrorLogger()

Wikimedia\Rdbms\Database::connectionErrorLogger ( $errno,
$errstr )

Error handler for logging errors during database connection.

Access: internal
This method should not be used outside of Database classes
Parameters
int | string$errno
string$errstr

Definition at line 565 of file Database.php.

◆ databasesAreIndependent()

Wikimedia\Rdbms\Database::databasesAreIndependent ( )

Returns true if DBs are assumed to be on potentially different servers.In systems like mysql/mariadb, different databases can easily be referenced on a single connection merely by name, even in a single query via JOIN. On the other hand, Postgres treats databases as logically separate, with different database users, requiring special mechanisms like postgres_fdw to "mount" foreign DBs. This is true even among DBs on the same server. Changing the selected database via selectDomain() requires a new connection.

Returns
bool
Since
1.29

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 1772 of file Database.php.

◆ dbSchema()

Wikimedia\Rdbms\Database::dbSchema ( $schema = null)

Get/set the db schema.

Parameters
string | null$schemaThe database schema to set, or omitted to leave it unchanged
Returns
string The previous db schema

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 410 of file Database.php.

Referenced by DatabaseInstaller\selectDatabase().

◆ decodeBlob()

Wikimedia\Rdbms\Database::decodeBlob ( $b)

Some DBMSs return a special placeholder object representing blob fields in result objects.Pass the object through this function to return the original string.

Parameters
string | Blob$b
Returns
string
Exceptions
DBError

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2991 of file Database.php.

◆ decodeExpiry()

Wikimedia\Rdbms\Database::decodeExpiry ( $expiry,
$format = TS_MW )

Decode an expiry time into a DBMS independent format.

Parameters
string$expiryDB timestamp field value for expiry
int$formatTS_* constant, defaults to TS_MW
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3775 of file Database.php.

◆ delete()

Wikimedia\Rdbms\Database::delete ( $table,
$conds,
$fname = __METHOD__ )

Delete all rows in a table that match a condition.

This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.

Parameters
string$tableTable name
string | array$condsArray of conditions. See $conds in IDatabase::select() In order to prevent possible performance or replication issues or damaging a data accidentally, an empty condition for 'delete' queries isn't allowed. IDatabase::ALL_ROWS should be passed explicitly in order to delete all rows.
string$fnameName of the calling function
Returns
bool Return true if no exception was thrown (deprecated since 1.33)
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2019 of file Database.php.

◆ deleteJoin()

Wikimedia\Rdbms\Database::deleteJoin ( $delTable,
$joinTable,
$delVar,
$joinVar,
$conds,
$fname = __METHOD__ )

Delete all rows in a table that match a condition which includes a join.For safety, an empty $conds will not delete everything. If you want to delete all rows where the join condition matches, set $conds=IDatabase::ALL_ROWS.DO NOT put the join condition in $conds.This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.

Parameters
string$delTableThe table to delete from.
string$joinTableThe reference table used by the join (not modified).
string$delVarThe variable to join on, in the first table.
string$joinVarThe variable to join on, in the second table.
array | string$condsCondition array of field names mapped to variables, ANDed together in the WHERE clause
string$fnameCalling function name (use METHOD) for logs/profiling
Exceptions
DBErrorIf an error occurs, {
See also
query}

Stability: stable
to override

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 1983 of file Database.php.

◆ doAtomicSection()

Wikimedia\Rdbms\Database::doAtomicSection ( $fname,
callable $callback,
$cancelable = self::ATOMIC_NOT_CANCELABLE )
final

Perform an atomic section of reversible SQL statements from a callback.

The $callback takes the following arguments:

  • This database object
  • The value of $fname

This will execute the callback inside a pair of startAtomic()/endAtomic() calls. If any exception occurs during execution of the callback, it will be handled as follows:

  • If $cancelable is ATOMIC_CANCELABLE, cancelAtomic() will be called to back out any (and only) statements executed during the atomic section. If that succeeds, then the exception will be re-thrown; if it fails, then a different exception will be thrown and any further query attempts will fail until rollback() is called.
  • If $cancelable is ATOMIC_NOT_CANCELABLE, cancelAtomic() will be called to mark the end of the section and the error will be re-thrown. Any further query attempts will fail until rollback() is called.

This method is convenient for letting calls to the caller of this method be wrapped in a try/catch blocks for exception types that imply that the caller failed but was able to properly discard the changes it made in the transaction. This method can be an alternative to explicit calls to startAtomic()/endAtomic()/cancelAtomic().

Example usage, "RecordStore::save" method:

$dbw->doAtomicSection( __METHOD__, function ( $dbw ) use ( $record ) {
// Create new record metadata row
$dbw->insert( 'records', $record->toArray(), __METHOD__ );
// Figure out where to store the data based on the new row's ID
$path = $this->recordDirectory . '/' . $dbw->insertId();
// Write the record data to the storage system;
// blob store throws StoreFailureException on failure
$this->blobStore->create( $path, $record->getJSON() );
// Try to cleanup files orphaned by transaction rollback
$dbw->onTransactionResolution(
function ( $type ) use ( $path ) {
if ( $type === IDatabase::TRIGGER_ROLLBACK ) {
$this->blobStore->delete( $path );
}
},
__METHOD__
);
}, $dbw::ATOMIC_CANCELABLE );

Example usage, caller of the "RecordStore::save" method:

$dbw->startAtomic( __METHOD__ );
// ...various SQL writes happen...
try {
$recordStore->save( $record );
} catch ( StoreFailureException $e ) {
// ...various SQL writes happen...
}
// ...various SQL writes happen...
$dbw->endAtomic( __METHOD__ );
See also
Database::startAtomic
Database::endAtomic
Database::cancelAtomic
Parameters
string$fnameCaller name (usually METHOD)
callable$callbackCallback that issues write queries
string$cancelablePass self::ATOMIC_CANCELABLE to use a savepoint and enable self::cancelAtomic() for this section.
Returns
mixed Result of the callback (since 1.28)
Exceptions
DBErrorIf an error occurs, {
See also
query}
Exceptions
ExceptionIf an error occurs in the callback
Since
1.27; prior to 1.31 this did a rollback() instead of cancelAtomic(), and assumed no callers up the stack would ever try to catch the exception.

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2604 of file Database.php.

References $res.

◆ doBegin()

Wikimedia\Rdbms\Database::doBegin ( $fname)
protected

Issues the BEGIN command to the database server.

See also
Database::begin()
Stability: stable
to override
Parameters
string$fname
Exceptions
DBError

Reimplemented in Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2665 of file Database.php.

◆ doCommit()

Wikimedia\Rdbms\Database::doCommit ( $fname)
protected

Issues the COMMIT command to the database server.

Stability: stable
to override
See also
Database::commit()
Parameters
string$fname
Exceptions
DBError

Definition at line 2711 of file Database.php.

◆ doFlushSession()

Wikimedia\Rdbms\Database::doFlushSession ( $fname)
protected

Reset the server-side session state for named locks and table locks.

Connection and query errors will be suppressed and logged

Parameters
string$fname
Since
1.38

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2815 of file Database.php.

◆ doHandleSessionLossPreconnect()

Wikimedia\Rdbms\Database::doHandleSessionLossPreconnect ( )
protected

Reset any additional subclass trx* and session* fields.

Stability: stable
to override

Reimplemented in Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 1431 of file Database.php.

◆ doInitConnection()

Wikimedia\Rdbms\Database::doInitConnection ( )
protected

Actually connect to the database over the wire (or to local files)

Exceptions
DBConnectionError
Since
1.31

Definition at line 273 of file Database.php.

References Wikimedia\Rdbms\Database\open().

Referenced by Wikimedia\Rdbms\Database\initConnection().

◆ doInsertSelectGeneric()

Wikimedia\Rdbms\Database::doInsertSelectGeneric ( $destTable,
$srcTable,
array $varMap,
$conds,
$fname,
array $insertOptions,
array $selectOptions,
$selectJoinConds )
protected

Implementation of insertSelect() based on select() and insert()

See also
IDatabase::insertSelect()
Parameters
string$destTable
string | array$srcTable
array$varMap
array$conds
string$fname
array$insertOptions
array$selectOptions
array$selectJoinConds
Since
1.35

Definition at line 2095 of file Database.php.

References $res.

◆ doInsertSelectNative()

Wikimedia\Rdbms\Database::doInsertSelectNative ( $destTable,
$srcTable,
array $varMap,
$conds,
$fname,
array $insertOptions,
array $selectOptions,
$selectJoinConds )
protected

Native server-side implementation of insertSelect() for situations where we don't want to select everything into memory.

See also
IDatabase::insertSelect()
Parameters
string$destTable
string | array$srcTable
array$varMap
array$conds
string$fname
array$insertOptions
array$selectOptions
array$selectJoinConds
Since
1.35

Reimplemented in Wikimedia\Rdbms\DatabasePostgres.

Definition at line 2160 of file Database.php.

◆ doLock()

Wikimedia\Rdbms\Database::doLock ( string $lockName,
string $method,
int $timeout )
protected
See also
lock()
Parameters
string$lockName
string$method
int$timeout
Returns
float|null UNIX timestamp of lock acquisition; null on failure
Exceptions
DBError
Stability: stable
to override

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 3195 of file Database.php.

◆ doLockIsFree()

Wikimedia\Rdbms\Database::doLockIsFree ( string $lockName,
string $method )
protected
See also
lockIsFree()
Parameters
string$lockName
string$method
Returns
bool Success
Exceptions
DBError
Stability: stable
to override

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 3156 of file Database.php.

◆ doMultiStatementQuery()

Wikimedia\Rdbms\Database::doMultiStatementQuery ( array $sqls)
protected

Execute a batch of query statements, aborting remaining statements if one fails.

See also
Database::doQuery()
Stability: stable
to override
Parameters
string[]$sqlsNon-empty map of (statement ID => SQL statement)
Returns
array<string,QueryStatus> Map of (statement ID => QueryStatus)
Since
1.39

Reimplemented in Wikimedia\Rdbms\DatabaseMysqli, and Wikimedia\Rdbms\DatabasePostgres.

Definition at line 711 of file Database.php.

◆ doReplace()

Wikimedia\Rdbms\Database::doReplace ( $table,
array $identityKey,
array $rows,
$fname )
protected
Parameters
string$table
string[]$identityKeyList of columns defining a unique key
array$rowsNon-empty list of rows
string$fname
See also
Database::replace()
Stability: stable
to override
Since
1.35

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 1858 of file Database.php.

◆ doSelectDomain()

Wikimedia\Rdbms\Database::doSelectDomain ( DatabaseDomain $domain)
protected
Stability: stable
to override
Parameters
DatabaseDomain$domain
Exceptions
DBConnectionError
DBError
Since
1.32

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 1796 of file Database.php.

◆ doSingleStatementQuery()

Wikimedia\Rdbms\Database::doSingleStatementQuery ( string $sql)
abstractprotected

Run a query and return a QueryStatus instance with the query result information.

This is meant to handle the basic command of actually sending a query to the server via the driver. No implicit transaction, reconnection, nor retry logic should happen here. The higher level query() method is designed to handle those sorts of concerns. This method should not trigger such higher level methods.

The lastError() and lastErrno() methods should meaningfully reflect what error, if any, occurred during the last call to this method. Methods like executeQuery(), query(), select(), insert(), update(), delete(), and upsert() implement their calls to doQuery() such that an immediately subsequent call to lastError()/lastErrno() meaningfully reflects any error that occurred during that public query method call.

For SELECT queries, the result field contains either:

  • a) A driver-specific IResultWrapper describing the query results
  • b) False, on any query failure

For non-SELECT queries, the result field contains either:

  • a) A driver-specific IResultWrapper, only on success
  • b) True, only on success (e.g. no meaningful result other than "OK")
  • c) False, on any query failure
Parameters
string$sqlSingle-statement SQL query
Returns
QueryStatus
Since
1.39

Reimplemented in Wikimedia\Rdbms\DatabaseMysqli, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

◆ doTruncate()

Wikimedia\Rdbms\Database::doTruncate ( array $tables,
$fname )
protected
See also
Database::truncate()
Stability: stable
to override
Parameters
string[]$tables
string$fname

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 3299 of file Database.php.

◆ doUnlock()

Wikimedia\Rdbms\Database::doUnlock ( string $lockName,
string $method )
protected
See also
unlock()
Parameters
string$lockName
string$method
Returns
bool Success
Exceptions
DBError
Stability: stable
to override

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 3225 of file Database.php.

◆ doUpsert()

Wikimedia\Rdbms\Database::doUpsert ( string $table,
array $rows,
array $identityKey,
array $set,
string $fname )
protected

Perform an UPSERT query.

See also
Database::upsert()
Database::buildExcludedValue()
Stability: stable
to override
Parameters
string$tableTable name
array[]$rowsNon-empty list of rows to insert
string[]$identityKeyColumns of the (unique) identity key to UPSERT upon
string[]$setNon-empty map of (column name => SQL expression or literal)
string$fname
Since
1.35

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase.

Definition at line 1910 of file Database.php.

◆ dropTable()

Wikimedia\Rdbms\Database::dropTable ( $table,
$fname = __METHOD__ )

Delete a table.

Parameters
string$table
string$fname
Returns
bool Whether the table already existed
Exceptions
DBErrorIf an error occurs

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 3265 of file Database.php.

◆ duplicateTableStructure()

Wikimedia\Rdbms\Database::duplicateTableStructure ( $oldName,
$newName,
$temporary = false,
$fname = __METHOD__ )

Creates a new table with structure copied from existing table.Note that unlike most database abstraction functions, this function does not automatically append database prefix, because it works at a lower abstraction level. The table names passed to this function shall not be quoted (this function calls addIdentifierQuotes() when needed).

Parameters
string$oldNameName of table whose structure should be copied
string$newNameName of table to be created
bool$temporaryWhether the new table should be temporary
string$fnameCalling function name
Returns
bool True if operation was successful
Exceptions
RuntimeException

Stability: stable
to override

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2828 of file Database.php.

◆ encodeBlob()

Wikimedia\Rdbms\Database::encodeBlob ( $b)

Some DBMSs have a special format for inserting into blob fields, they don't allow simple quoted strings to be inserted.To insert into such a field, pass the data through this function before passing it to IDatabase::insert().

Parameters
string$b
Returns
string|Blob
Exceptions
DBError

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2983 of file Database.php.

◆ encodeExpiry()

Wikimedia\Rdbms\Database::encodeExpiry ( $expiry)

Encode an expiry time into the DBMS dependent format.

Parameters
string$expiryTimestamp for expiry, or the 'infinity' string
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3771 of file Database.php.

◆ endAtomic()

Wikimedia\Rdbms\Database::endAtomic ( $fname = __METHOD__)
final

Ends an atomic section of SQL statements.

Ends the next section of atomic SQL statements and commits the transaction if necessary.

Since
1.23
See also
IDatabase::startAtomic
Parameters
string$fname
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2500 of file Database.php.

◆ estimateRowCount()

Wikimedia\Rdbms\Database::estimateRowCount ( $tables,
$var = '*',
$conds = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Estimate the number of rows in dataset.MySQL allows you to estimate the number of rows that would be returned by a SELECT query, using EXPLAIN SELECT. The estimate is provided using index cardinality statistics, and is notoriously inaccurate, especially when large numbers of rows have recently been added or deleted.For DBMSs that don't support fast result size estimation, this function will actually perform the SELECT COUNT(*).Takes the same arguments as IDatabase::select().New callers should use newSelectQueryBuilder with SelectQueryBuilder::estimateRowCount instead, which is more readable and less error-prone.

Parameters
string | string[]$tablesTable name(s)
string$varColumn for which NULL values are not counted [default "*"]
array | string$condsFilters on the table
string$fnameFunction name for profiling
array$optionsOptions for select
array | string$join_condsJoin conditions
Returns
int Row count
Exceptions
DBErrorIf an error occurs, {
See also
query}

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseMysqlBase.

Definition at line 1654 of file Database.php.

References $res.

◆ executeQuery()

Wikimedia\Rdbms\Database::executeQuery ( $sqls,
$fname,
$flags,
$summarySql )
finalprotected

Execute a set of queries without enforcing public (non-Database) caller restrictions.

Retry it if there is a recoverable connection loss (e.g. no important state lost).

This does not precheck for transaction/session state errors or critical section errors.

See also
Database::query()
Database::querMulti()
Parameters
string | string[]$sqlsSQL statment or (statement ID => SQL statement) map
string$fnameName of the calling function
int$flagsBit field of class QUERY_* constants
string$summarySqlWhole or simplified SQL for profiling
Returns
QueryStatus|array<string,QueryStatus> QueryStatus (when given a string statement) or ordered map of (statement ID => QueryStatus) (when given an array of statements)
Exceptions
DBUnexpectedError
Since
1.34

Definition at line 918 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\doFlushSession(), Wikimedia\Rdbms\DatabaseMysqlBase\doSelectDomain(), and Wikimedia\Rdbms\DatabaseMysqlBase\open().

◆ explicitTrxActive()

Wikimedia\Rdbms\Database::explicitTrxActive ( )

Check whether there is a transaction open at the specific request of a caller.

Explicit transactions are spawned by begin(), startAtomic(), and doAtomicSection(). Note that explicit transactions should not be confused with explicit transaction rounds.

Returns
bool
Since
1.28

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3613 of file Database.php.

◆ factorConds()

Wikimedia\Rdbms\Database::factorConds ( $condsArray)

Given an array of condition arrays representing an OR list of AND lists, for example:

(A=1 AND B=2) OR (A=1 AND B=3)

produce an SQL expression in which the conditions are factored:

(A=1 AND (B=2 OR B=3))

We also use IN() to simplify further:

(A=1 AND (B IN (2,3))

More compactly, in boolean algebra notation, a sum of products, e.g. AB + AC is factored to produce A(B+C). Factoring proceeds recursively to reduce expressions with any number of variables, for example AEP + AEQ + AFP + AFQ = A(E(P+Q) + F(P+Q))

The algorithm is simple and will not necessarily find the shortest possible expression. For the best results, fields should be given in a consistent order, and the fields with values likely to be shared should be leftmost in the associative arrays.

Parameters
array$condsArrayAn array of associative arrays. The associative array keys represent field names, and the values represent the field values to compare against.
Returns
string SQL expression fragment

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3643 of file Database.php.

◆ factory()

static Wikimedia\Rdbms\Database::factory ( $type,
$params = [],
$connect = self::NEW_CONNECTED )
staticfinal

Construct a Database subclass instance given a database type and parameters.

This also connects to the database immediately upon object construction

Parameters
string$typeA possible DB type (sqlite, mysql, postgres,...)
array$paramsParameter map with keys:
  • host : The hostname or IP address of the database server
  • user : The name of the database user the client operates under
  • password : The password for the database user
  • dbname : The name of the database to use where queries do not specify one. The database must exist or an error might be thrown. Setting this to an empty string will avoid any such errors and make the handle have no implicit database scope. This is useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a "database" in Postgres is roughly equivalent to an entire MySQL server. This the domain in which user names and such are defined, e.g. users are database-specific in Postgres.
  • schema : The database schema to use (if supported). A "schema" in Postgres is roughly equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
  • tablePrefix : Optional table prefix that is implicitly added on to all table names recognized in queries. This can be used in place of schemas for handle site farms.
  • flags : Optional bit field of DBO_* constants that define connection, protocol, buffering, and transaction behavior. It is STRONGLY advised to leave the DBO_DEFAULT flag in place UNLESS this database simply acts as a key/value store.
  • ssl : Whether to use TLS connections.
  • driver: Optional name of a specific DB client driver. For MySQL, there is only the 'mysqli' driver; the old one 'mysql' has been removed.
  • variables: Optional map of session variables to set after connecting. This can be used to adjust lock timeouts or encoding modes and the like.
  • serverName : Optional readable name for the database server.
  • topologyRole: Optional IDatabase::ROLE_* constant that defines the replication role that this server plays within the parent database cluster.
  • lbInfo: Optional map of field/values for the managing load balancer instance. The "master" and "replica" fields are used to flag the replication role of this database server and whether methods like getLag() should actually issue queries.
  • connectTimeout: Optional timeout, in seconds, for connection attempts.
  • receiveTimeout: Optional timeout, in seconds, for receiving query results.
  • logger: Optional PSR-3 logger interface instance.
  • profiler : Optional callback that takes a section name argument and returns a ScopedCallback instance that ends the profile section in its destructor. These will be called in query(), using a simplified version of the SQL that also includes the agent as a SQL comment.
  • trxProfiler: Optional TransactionProfiler instance.
  • errorLogger: Optional callback that takes an Exception and logs it.
  • deprecationLogger: Optional callback that takes a string and logs it.
  • cliMode: Whether to consider the execution context that of a CLI script.
  • agent: Optional name used to identify the end-user in query profiling/logging.
  • srvCache: Optional BagOStuff instance to an APC-style cache.
  • nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT.
  • criticalSectionProvider: Optional CriticalSectionProvider instance.
int$connectOne of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
Returns
Database|null If the database driver or extension cannot be found
Exceptions
InvalidArgumentExceptionIf the database driver or extension cannot be found
Deprecated
since 1.39, use DatabaseFactory::create instead
Since
1.18

Definition at line 352 of file Database.php.

References $type, and wfDeprecated().

◆ fetchAffectedRowCount()

Wikimedia\Rdbms\Database::fetchAffectedRowCount ( )
abstractprotected
Returns
int Number of retrieved rows according to the driver

Reimplemented in Wikimedia\Rdbms\DatabaseMysqli, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

◆ fieldExists()

Wikimedia\Rdbms\Database::fieldExists ( $table,
$field,
$fname = __METHOD__ )

Determines whether a field exists in a table.

Parameters
string$tableTable name
string$fieldField to check on that table
string$fnameCalling function name (optional)
Returns
bool Whether $table has field $field
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 1716 of file Database.php.

◆ flushSession()

Wikimedia\Rdbms\Database::flushSession ( $fname = __METHOD__,
$flush = self::FLUSHING_ONE )

Release important session-level state (named lock, table locks) as post-rollback cleanup.

This should only be called by a load balancer or if the handle is not attached to one. Also, there must be no chance that a future caller will still be expecting some of the lost session state.

Connection and query errors will be suppressed and logged

Parameters
string$fnameCalling function name
string$flushFlush flag, set to a situationally valid IDatabase::FLUSHING_* constant to disable warnings about explicitly rolling back implicit transactions. This will silently break any ongoing explicit transaction. Only set the flush flag if you are sure that it is safe to ignore these warnings in your context.
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.38

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2768 of file Database.php.

◆ flushSnapshot()

Wikimedia\Rdbms\Database::flushSnapshot ( $fname = __METHOD__,
$flush = self::FLUSHING_ONE )

Commit any transaction but error out if writes or callbacks are pending.

This is intended for clearing out REPEATABLE-READ snapshots so that callers can see a new point-in-time of the database. This is useful when one of many transaction rounds finished and significant time will pass in the script's lifetime. It is also useful to call on a replica server after waiting on replication to catch up to the primary server.

Parameters
string$fnameCalling function name
string$flushFlush flag, set to situationally valid IDatabase::FLUSHING_* constant to disable warnings about explicitly committing implicit transactions, or calling commit when no transaction is in progress. This will trigger an exception if there is an ongoing explicit transaction. Only set the flush flag if you are sure that these warnings are not applicable, and no explicit transactions are open.
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.28
1.34 Added $flush parameter

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2819 of file Database.php.

◆ getAttributes()

static Wikimedia\Rdbms\Database::getAttributes ( )
static
Stability: stable
to override
Returns
array Map of (Database::ATTR_* constant => value)
Since
1.31

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 362 of file Database.php.

◆ getBindingHandle()

Wikimedia\Rdbms\Database::getBindingHandle ( )
protected

Get the underlying binding connection handle.

Makes sure the connection resource is set (disconnects and ping() failure can unset it). This catches broken callers than catch and ignore disconnection exceptions. Unlike checking isOpen(), this is safe to call inside of open().

Stability: stable
to override
Returns
mixed
Exceptions
DBUnexpectedError
Since
1.26

Reimplemented in Wikimedia\Rdbms\DatabaseMysqli, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 3339 of file Database.php.

◆ getCacheSetOptions()

static Wikimedia\Rdbms\Database::getCacheSetOptions ( ?IDatabase ... $dbs)
static

Merge the result of getSessionLagStatus() for several DBs using the most pessimistic values to estimate the lag of any data derived from them in combination.

This is information is useful for caching modules

See also
WANObjectCache::set()
WANObjectCache::getWithSetCallback()
Parameters
IDatabase|null...$dbs Note: For backward compatibility, it is allowed for null values to be passed among the parameters. This is deprecated since 1.36, only IDatabase objects should be passed.
Returns
array Map of values:
  • lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
  • since: oldest UNIX timestamp of any of the DB lag estimates
  • pending: whether any of the DBs have uncommitted changes
Exceptions
DBError
Since
1.27

Definition at line 2959 of file Database.php.

References $res.

Referenced by MediaWiki\Storage\NameTableStore\getName(), BacklinkCache\getNumLinks(), MediaWiki\Block\DatabaseBlock\isExemptedFromAutoblocks(), User\loadFromCache(), BacklinkCache\partition(), and MediaWiki\ResourceLoader\MessageBlobStore\recacheMessageBlob().

◆ getDBname()

◆ getDomainID()

Wikimedia\Rdbms\Database::getDomainID ( )

Return the currently selected domain ID.

Null components (database/schema) might change once a connection is established

Returns
string

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 496 of file Database.php.

◆ getFlag()

Wikimedia\Rdbms\Database::getFlag ( $flag)

Returns a boolean whether the flag $flag is set for this connection.

Parameters
int$flagOne of the class IDatabase::DBO_* constants
Returns
bool

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 3553 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseSqlite\open().

◆ getInfinity()

Wikimedia\Rdbms\Database::getInfinity ( )

Find out when 'infinity' is.

Most DBMSes support this. This is a special keyword for timestamps in PostgreSQL, and works with CHAR(14) as well because "i" sorts after all numbers.

Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3767 of file Database.php.

◆ getLag()

Wikimedia\Rdbms\Database::getLag ( )

Get the amount of replication lag for this database server.

Callers should avoid using this method while a transaction is active

Returns
float|int|false Database replication lag in seconds or false on error
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 3835 of file Database.php.

◆ getLastPHPError()

Wikimedia\Rdbms\Database::getLastPHPError ( )
protected
Returns
string|false Last PHP error for this DB (typically connection errors)

Definition at line 546 of file Database.php.

◆ getLBInfo()

Wikimedia\Rdbms\Database::getLBInfo ( $name = null)

Get properties passed down from the server info array of the load balancer.

Parameters
string | null$nameThe entry of the info array to get, or null to get the whole array
Returns
array|mixed|null

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 433 of file Database.php.

◆ getLogContext()

Wikimedia\Rdbms\Database::getLogContext ( array $extras = [])
protected

Create a log context to pass to PSR-3 logger functions.

Parameters
array$extrasAdditional data to add to context
Returns
array

Definition at line 575 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseSqlite\open().

◆ getPrimaryPos()

Wikimedia\Rdbms\Database::getPrimaryPos ( )

Get the position of this primary DB.

Returns
DBPrimaryPos|false False if this is not a primary DB
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.37

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3823 of file Database.php.

◆ getReadOnlyReason()

Wikimedia\Rdbms\Database::getReadOnlyReason ( )
protected
Returns
array|false Tuple of (read-only reason, "role" or "lb") or false if it is not

Definition at line 3313 of file Database.php.

◆ getReplicaPos()

Wikimedia\Rdbms\Database::getReplicaPos ( )

Get the replication position of this replica DB.

Returns
DBPrimaryPos|false False if this is not a replica DB
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 3819 of file Database.php.

◆ getScopedLockAndFlush()

Wikimedia\Rdbms\Database::getScopedLockAndFlush ( $lockKey,
$fname,
$timeout )

Acquire a named lock, flush any transaction, and return an RAII style unlocker object.

Only call this from outer transaction scope and when only one DB server will be affected. See https://www.mediawiki.org/wiki/Database_transactions for details.

This is suitable for transactions that need to be serialized using cooperative locks, where each transaction can see each others' changes. Any transaction is flushed to clear out stale REPEATABLE-READ snapshot data. Once the returned object falls out of PHP scope, the lock will be released unless a transaction is active. If one is active, then the lock will be released when it either commits or rolls back.

If the lock acquisition failed, then no transaction flush happens, and null is returned.

Parameters
string$lockKeyName of lock to release
string$fnameName of the calling method
int$timeoutAcquisition timeout in seconds
Returns
ScopedCallback|null
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.27

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3229 of file Database.php.

◆ getServer()

Wikimedia\Rdbms\Database::getServer ( )

Get the hostname or IP address of the server.

Returns
string|null

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1805 of file Database.php.

Referenced by Wikimedia\Rdbms\LoadBalancerSingle\__construct().

◆ getServerInfo()

Wikimedia\Rdbms\Database::getServerInfo ( )

Get a human-readable string describing the current software version.

Use getServerVersion() to get machine-friendly information.

Returns
string Version information from the database server

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 375 of file Database.php.

References Wikimedia\Rdbms\IReadableDatabase\getServerVersion().

◆ getServerName()

Wikimedia\Rdbms\Database::getServerName ( )

Get the readable name for the server.

Returns
string Readable server name, falling back to the hostname or IP address
Since
1.36

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1809 of file Database.php.

◆ getSessionLagStatus()

Wikimedia\Rdbms\Database::getSessionLagStatus ( )

Get the replica server lag when the current transaction started or a general lag estimate if not transaction is active.

This is useful when transactions might use snapshot isolation (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data is this lag plus transaction duration. If they don't, it is still safe to be pessimistic. In AUTOCOMMIT mode, this still gives an indication of the staleness of subsequent reads.

Returns
array ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.27

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 3839 of file Database.php.

◆ getTableAliases()

Wikimedia\Rdbms\Database::getTableAliases ( )

Return current table aliases.

Access: internal
only to be used inside rdbms library

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3783 of file Database.php.

◆ getTempTableWrites()

Wikimedia\Rdbms\Database::getTempTableWrites ( $sql,
$pseudoPermanent )
protected
Parameters
string$sqlSQL query
bool$pseudoPermanentTreat any table from CREATE TEMPORARY as pseudo-permanent
Returns
array[] List of change n-tuples with:
  • int: self::TEMP_* constant for temp table operations
  • string: SQL query verb from $sql
  • string: Name of the temp table changed in $sql

Definition at line 734 of file Database.php.

◆ getTopologyBasedServerId()

Wikimedia\Rdbms\Database::getTopologyBasedServerId ( )

Get a non-recycled ID that uniquely identifies this server within the replication topology.

A replication topology defines which servers can originate changes to a given dataset and how those changes propagate among database servers. It is assumed that the server only participates in the replication of a single relevant dataset.

Returns
string|null 32, 64, or 128 bit integer ID; null if not applicable or unknown
Exceptions
DBQueryError
Since
1.37

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3831 of file Database.php.

◆ getTopologyRole()

Wikimedia\Rdbms\Database::getTopologyRole ( )

Get the replication topology role of this server.

A replication topology defines which servers can originate changes to a given dataset and how those changes propagate among database servers. It is assumed that the server only participates in the replication of a single relevant dataset.

Returns
string One of the class ROLE_* constants
Exceptions
DBQueryError
Since
1.34

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3827 of file Database.php.

◆ getTransactionRoundId()

Wikimedia\Rdbms\Database::getTransactionRoundId ( )
finalprotected
Returns
string|null ID of the active explicit transaction round being participating in

Definition at line 480 of file Database.php.

◆ getValueTypesForWithClause()

Wikimedia\Rdbms\Database::getValueTypesForWithClause ( $table)
Parameters
string$table
Returns
array<string,string>

Reimplemented in Wikimedia\Rdbms\DatabasePostgres.

Definition at line 1975 of file Database.php.

◆ implicitOrderby()

Wikimedia\Rdbms\Database::implicitOrderby ( )

Returns true if this database does an implicit order by when the column has an index For example: SELECT page_title FROM page LIMIT 1.

Returns
bool

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3621 of file Database.php.

◆ indexExists()

Wikimedia\Rdbms\Database::indexExists ( $table,
$index,
$fname = __METHOD__ )

Determines whether an index exists.

Parameters
string$table
string$index
string$fname
Returns
bool|null
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 1722 of file Database.php.

◆ indexInfo()

Wikimedia\Rdbms\Database::indexInfo ( $table,
$index,
$fname = __METHOD__ )
abstract

Get information about an index into an object.

Stability: stable
to override
Parameters
string$tableTable name
string$indexIndex name
string$fnameCalling function name
Returns
mixed Database-specific index description class or false if the index does not exist

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

◆ indexName()

Wikimedia\Rdbms\Database::indexName ( $index)
protected

Definition at line 3695 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\indexInfo().

◆ indexUnique()

Wikimedia\Rdbms\Database::indexUnique ( $table,
$index,
$fname = __METHOD__ )

Determines if a given index is unique.

Parameters
string$table
string$index
string$fnameCalling function name
Returns
bool

Stability: stable
to override

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 1741 of file Database.php.

◆ initConnection()

Wikimedia\Rdbms\Database::initConnection ( )
final

Initialize the connection to the database over the wire (or to local files)

Exceptions
LogicException
InvalidArgumentException
DBConnectionError
Since
1.31

Definition at line 258 of file Database.php.

References Wikimedia\Rdbms\Database\doInitConnection(), and Wikimedia\Rdbms\Database\isOpen().

◆ insert()

Wikimedia\Rdbms\Database::insert ( $table,
$rows,
$fname = __METHOD__,
$options = [] )

Insert row(s) into a table, in the provided order.

This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.

Parameters
string$tableTable name
array | array[]$rowsRow(s) to insert, as either:
  • A string-keyed map of (column name => value) defining a new row. Values are treated as literals and quoted appropriately; null is interpreted as NULL.
  • An integer-keyed list of such string-keyed maps, defining a list of new rows. The keys in each map must be identical to each other and in the same order. The rows must not collide with each other.
string$fnameCalling function name (use METHOD) for logs/profiling
string | array$optionsCombination map/list where each string-keyed entry maps a non-boolean option to the option parameters and each integer-keyed value is the name of a boolean option. Supported options are:
  • IGNORE: Boolean: skip insertion of rows that would cause unique key conflicts. IDatabase::affectedRows() can be used to determine how many rows were inserted.
Returns
bool Return true if no exception was thrown (deprecated since 1.33)
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 1751 of file Database.php.

◆ insertSelect()

Wikimedia\Rdbms\Database::insertSelect ( $destTable,
$srcTable,
$varMap,
$conds,
$fname = __METHOD__,
$insertOptions = [],
$selectOptions = [],
$selectJoinConds = [] )
final

INSERT SELECT wrapper.

Warning
If the insert will use an auto-increment or sequence to determine the value of a column, this may break replication on databases using statement-based replication if the SELECT is not deterministically ordered.

This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.

Parameters
string$destTableThe table name to insert into
string | array$srcTableMay be either a table name, or an array of table names to include in a join.
array$varMapMust be an associative array of the form [ 'dest1' => 'source1', ... ]. Source items may be literals rather than field names, but strings should be quoted with IDatabase::addQuotes()
array$condsCondition array. See $conds in IDatabase::select() for the details of the format of condition arrays. May be "*" to copy the whole table.
string$fnameThe function name of the caller, from METHOD
array$insertOptionsOptions for the INSERT part of the query, see IDatabase::insert() for details. Also, one additional option is available: pass 'NO_AUTO_COLUMNS' to hint that the query does not use an auto-increment or sequence to determine any column values.
array$selectOptionsOptions for the SELECT part of the query, see IDatabase::select() for details.
array$selectJoinCondsJoin conditions for the SELECT part of the query, see IDatabase::select() for details.
Returns
bool Return true if no exception was thrown (deprecated since 1.33)
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2026 of file Database.php.

◆ installErrorHandler()

Wikimedia\Rdbms\Database::installErrorHandler ( )
protected

Set a custom error handler for logging errors during database connection.

Definition at line 523 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\open(), and Wikimedia\Rdbms\DatabasePostgres\open().

◆ isConnectionError()

Wikimedia\Rdbms\Database::isConnectionError ( $errno)
protected

Do not use this method outside of Database/DBError classes.

Stability: stable
to override
Parameters
int | string$errno
Returns
bool Whether the given query error was a connection drop
Since
1.38

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2231 of file Database.php.

◆ isInsertSelectSafe()

Wikimedia\Rdbms\Database::isInsertSelectSafe ( array $insertOptions,
array $selectOptions )
protected
Stability: stable
to override
Parameters
array$insertOptions
array$selectOptions
Returns
bool Whether an INSERT SELECT with these options will be replication safe
Since
1.31

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase.

Definition at line 2077 of file Database.php.

◆ isKnownStatementRollbackError()

Wikimedia\Rdbms\Database::isKnownStatementRollbackError ( $errno)
protected
Stability: stable
to override
Parameters
int | string$errno
Returns
bool Whether it is known that the last query error only caused statement rollback
Note
This is for backwards compatibility for callers catching DBError exceptions in order to ignore problems like duplicate key errors or foreign key violations
Since
1.39

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2243 of file Database.php.

◆ isOpen()

Wikimedia\Rdbms\Database::isOpen ( )
Returns
bool Whether a connection to the database open

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 492 of file Database.php.

Referenced by Wikimedia\Rdbms\Database\initConnection().

◆ isPristineTemporaryTable()

Wikimedia\Rdbms\Database::isPristineTemporaryTable ( $table)
protected

Check if the table is both a TEMPORARY table and has not yet received CRUD operations.

Parameters
string$table
Returns
bool
Since
1.35

Definition at line 830 of file Database.php.

◆ isQueryTimeoutError()

Wikimedia\Rdbms\Database::isQueryTimeoutError ( $errno)
protected

Checks whether the cause of the error is detected to be a timeout.

It returns false by default, and not all engines support detecting this yet. If this returns false, it will be treated as a generic query error.

Stability: stable
to override
Parameters
int | string$errnoError number
Returns
bool
Since
1.39

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DatabasePostgres.

Definition at line 1458 of file Database.php.

◆ isQuotedIdentifier()

Wikimedia\Rdbms\Database::isQuotedIdentifier ( $name)

Definition at line 3703 of file Database.php.

◆ isReadOnly()

Wikimedia\Rdbms\Database::isReadOnly ( )
Returns
bool Whether this DB server is read-only
Since
1.27

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3306 of file Database.php.

◆ lastDoneWrites()

Wikimedia\Rdbms\Database::lastDoneWrites ( )

Get the last time the connection may have been used for a write query.

Returns
int|float|false UNIX timestamp or false
Since
1.24

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 464 of file Database.php.

◆ lastQuery()

Wikimedia\Rdbms\Database::lastQuery ( )

Get the last query that sent on account of IDatabase::query()

Deprecated
since 1.40 without replacement
Returns
string SQL text or empty string if there was no such query

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 459 of file Database.php.

References wfDeprecated().

◆ limitResult()

Wikimedia\Rdbms\Database::limitResult ( $sql,
$limit,
$offset = false )

Construct a LIMIT query with optional offset.

The SQL should be adjusted so that only the first $limit rows are returned. If $offset is provided as well, then the first $offset rows should be discarded, and the next $limit rows should be returned. If the result of the query is not ordered, then the rows to be returned are theoretically arbitrary.

$sql is expected to be a SELECT, if that makes a difference.

Parameters
string$sqlSQL query we will append the limit too
int$limitThe SQL limit
int | false$offsetThe SQL offset (default false)
Returns
string
Since
1.34 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3719 of file Database.php.

◆ listTables()

Wikimedia\Rdbms\Database::listTables ( $prefix = null,
$fname = __METHOD__ )

List all tables on the database.

Parameters
string | null$prefixOnly show tables with this prefix, e.g. mw_
string$fnameCalling function name
Exceptions
DBError
Returns
array

Stability: stable
to override

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2841 of file Database.php.

◆ listViews()

Wikimedia\Rdbms\Database::listViews ( $prefix = null,
$fname = __METHOD__ )

Lists all the VIEWs in the database.

Parameters
string | null$prefixOnly show VIEWs with this prefix, eg. unit_test_
string$fnameName of calling function
Exceptions
RuntimeException
Returns
array

Stability: stable
to override

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase.

Definition at line 2849 of file Database.php.

◆ lock()

Wikimedia\Rdbms\Database::lock ( $lockName,
$method,
$timeout = 5,
$flags = 0 )

Acquire a named lock.Named locks are not related to transactions

Parameters
string$lockNameName of lock to acquire
string$methodName of the calling method
int$timeoutAcquisition timeout in seconds (0 means non-blocking)
int$flagsBit field of IDatabase::LOCK_* constants
Returns
bool|float|null Success (bool); acquisition time (float/null) if LOCK_TIMESTAMP
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3163 of file Database.php.

◆ lockForUpdate()

Wikimedia\Rdbms\Database::lockForUpdate ( $table,
$conds = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Lock all rows meeting the given conditions/options FOR UPDATE.

Parameters
string | string[]$tableTable name(s)
array | string$condsFilters on the table
string$fnameFunction name for profiling
array$optionsOptions for select ("FOR UPDATE" is added automatically)
array$join_condsJoin conditions
Returns
int Number of matching rows found (and locked)
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.32

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 1700 of file Database.php.

◆ lockIsFree()

Wikimedia\Rdbms\Database::lockIsFree ( $lockName,
$method )

Check to see if a named lock is not locked by any thread (non-blocking)

Parameters
string$lockNameName of lock to poll
string$methodName of method calling us
Returns
bool
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.20

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3134 of file Database.php.

◆ makeList()

Wikimedia\Rdbms\Database::makeList ( array $a,
$mode = self::LIST_COMMA )

Makes an encoded list of strings from an array.

These can be used to make conjunctions or disjunctions on SQL condition strings derived from an array ({

See also
IDatabase::select} $conds documentation).

Example usage:

$sql = $db->makeList( [
'rev_page' => $id,
$db->makeList( [ 'rev_minor' => 1, 'rev_len < 500' ], $db::LIST_OR )
], $db::LIST_AND );

This would set $sql to "rev_page = '$id' AND (rev_minor = 1 OR rev_len < 500)"

Parameters
array$aContaining the data
int$modeIDatabase class constant:
  • IDatabase::LIST_COMMA: Comma separated, no field names
  • IDatabase::LIST_AND: ANDed WHERE clause (without the WHERE).
  • IDatabase::LIST_OR: ORed WHERE clause (without the WHERE)
  • IDatabase::LIST_SET: Comma separated with field names, like a SET clause
  • IDatabase::LIST_NAMES: Comma separated field names
Exceptions
DBErrorIf an error occurs, {
See also
IDatabase::query}
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3635 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\doUpsert().

◆ makeWhereFrom2d()

Wikimedia\Rdbms\Database::makeWhereFrom2d ( $data,
$baseKey,
$subKey )

Build a partial where clause from a 2-d array such as used for LinkBatch.

The keys on each level may be either integers or strings, however it's assumed that $baseKey is probably an integer-typed column (i.e. integer keys are unquoted in the SQL) and $subKey is string-typed (i.e. integer keys are quoted as strings in the SQL).

Todo
Does this actually belong in the library? It seems overly MW-specific.
Parameters
array$dataOrganized as 2-d [ baseKeyVal => [ subKeyVal => [ignored], ... ], ... ]
string$baseKeyField name to match the base-level keys to (eg 'pl_namespace')
string$subKeyField name to match the sub-level keys to (eg 'pl_title')
Returns
string|false SQL fragment, or false if no items in array

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3639 of file Database.php.

◆ namedLocksEnqueue()

Wikimedia\Rdbms\Database::namedLocksEnqueue ( )

Check to see if a named lock used by lock() use blocking queues.

Returns
bool
Since
1.26

Stability: stable
to override

Implements Wikimedia\Rdbms\IDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase.

Definition at line 3261 of file Database.php.

◆ newExceptionAfterConnectError()

Wikimedia\Rdbms\Database::newExceptionAfterConnectError ( $error)
finalprotected
Parameters
string$error
Returns
DBConnectionError

Definition at line 1532 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\open(), Wikimedia\Rdbms\DatabasePostgres\open(), and Wikimedia\Rdbms\DatabaseSqlite\open().

◆ newSelectQueryBuilder()

Wikimedia\Rdbms\Database::newSelectQueryBuilder ( )

Get a SelectQueryBuilder bound to this connection.

This is overridden by DBConnRef.

Returns
SelectQueryBuilder

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1556 of file Database.php.

◆ newUpdateQueryBuilder()

Wikimedia\Rdbms\Database::newUpdateQueryBuilder ( )

Get an UpdateQueryBuilder bound to this connection.

This is overridden by DBConnRef.

Returns
UpdateQueryBuilder

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 1566 of file Database.php.

◆ nextSequenceValue()

Wikimedia\Rdbms\Database::nextSequenceValue ( $seqName)

Deprecated method, calls should be removed.

This was formerly used for PostgreSQL to handle self::insertId() auto-incrementing fields. It is no longer necessary since DatabasePostgres::insertId() has been reimplemented using lastval()

Implementations should return null if inserting NULL into an auto-incrementing field works, otherwise it should return an instance of NextSequenceValue and filter it on calls to relevant methods.

Deprecated
since 1.30, no longer needed
Parameters
string$seqName
Returns
null|NextSequenceValue

Implements Wikimedia\Rdbms\IDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres.

Definition at line 1832 of file Database.php.

◆ onAtomicSectionCancel()

Wikimedia\Rdbms\Database::onAtomicSectionCancel ( callable $callback,
$fname = __METHOD__ )
final

Run a callback when the atomic section is cancelled.

The callback is run just after the current atomic section, any outer atomic section, or the whole transaction is rolled back.

An error is thrown if no atomic section is pending. The atomic section need not have been created with the ATOMIC_CANCELABLE flag.

Queries in the function may be running in the context of an outer transaction or may be running in AUTOCOMMIT mode. The callback should use atomic sections if necessary.

Note
do not assume that other IDatabase instances will be AUTOCOMMIT mode

The callback takes the following arguments:

  • IDatabase::TRIGGER_CANCEL or IDatabase::TRIGGER_ROLLBACK
  • This IDatabase instance
Parameters
callable$callback
string$fnameCaller name
Since
1.34

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2306 of file Database.php.

◆ onTransactionCommitOrIdle()

Wikimedia\Rdbms\Database::onTransactionCommitOrIdle ( callable $callback,
$fname = __METHOD__ )
final

Run a callback when the current transaction commits or now if there is none.

If there is a transaction and it is rolled back, then the callback is cancelled.

When transaction round mode (DBO_TRX) is set, the callback will run at the end of the round, just after all peer transactions COMMIT. If the transaction round is rolled back, then the callback is cancelled.

This IDatabase instance will start off in auto-commit mode when the callback starts. The use of other IDatabase handles from the callback should be avoided unless they are known to be in auto-commit mode. Callbacks that create transactions via begin() or startAtomic() must have matching calls to commit()/endAtomic().

Use this method only for the following purposes:

  • (a) RDBMS updates, prone to lock timeouts/deadlocks, that do not require atomicity with respect to the updates in the current transaction (if any)
  • (b) Purges to lightweight cache services due to RDBMS updates
  • (c) Updates to secondary DBs/stores that must only commit once the updates in the current transaction (if any) are committed (e.g. insert user account row to DB1, then, initialize corresponding LDAP account)

The callback takes the following arguments:

  • How the transaction ended (IDatabase::TRIGGER_COMMIT or IDatabase::TRIGGER_IDLE)
  • This IDatabase instance (since 1.32)

Callbacks will execute in the order they were enqueued.

Parameters
callable$callback
string$fnameCaller name
Exceptions
DBErrorIf an error occurs, {
See also
query}
Exceptions
ExceptionIf the callback runs immediately and an error occurs in it
Since
1.32

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2259 of file Database.php.

◆ onTransactionPreCommitOrIdle()

Wikimedia\Rdbms\Database::onTransactionPreCommitOrIdle ( callable $callback,
$fname = __METHOD__ )
final

Run a callback before the current transaction commits or now if there is none.

If there is a transaction and it is rolled back, then the callback is cancelled.

When transaction round mode (DBO_TRX) is set, the callback will run at the end of the round, just after all peer transactions COMMIT. If the transaction round is rolled back, then the callback is cancelled.

If there is no current transaction, one will be created to wrap the callback. Callbacks cannot use begin()/commit() to manage transactions. The use of other IDatabase handles from the callback should be avoided.

Use this method only for the following purposes:

  • a) RDBMS updates, prone to lock timeouts/deadlocks, that require atomicity with respect to the updates in the current transaction (if any)
  • b) Purges to lightweight cache services due to RDBMS updates

The callback takes the one argument:

  • This IDatabase instance (since 1.32)

Callbacks will execute in the order they were enqueued.

Parameters
callable$callback
string$fnameCaller name
Exceptions
DBErrorIf an error occurs, {
See also
query}
Exceptions
ExceptionIf the callback runs immediately and an error occurs in it
Since
1.22

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2277 of file Database.php.

◆ onTransactionResolution()

Wikimedia\Rdbms\Database::onTransactionResolution ( callable $callback,
$fname = __METHOD__ )
final

Run a callback when the current transaction commits or rolls back.

An error is thrown if no transaction is pending.

When transaction round mode (DBO_TRX) is set, the callback will run at the end of the round, just after all peer transactions COMMIT/ROLLBACK.

This IDatabase instance will start off in auto-commit mode when the callback starts. The use of other IDatabase handles from the callback should be avoided unless they are known to be in auto-commit mode. Callbacks that create transactions via begin() or startAtomic() must have matching calls to commit()/endAtomic().

Use this method only for the following purposes:

  • (a) Release of cooperative locks on resources
  • (b) Cancellation of in-process deferred tasks

The callback takes the following arguments:

  • How the current atomic section (if any) or overall transaction (otherwise) ended (IDatabase::TRIGGER_COMMIT or IDatabase::TRIGGER_ROLLBACK)
  • This IDatabase instance (since 1.32)

Callbacks will execute in the order they were enqueued.

Note
Use onAtomicSectionCancel() to take action as soon as an atomic section is cancelled
Parameters
callable$callback
string$fnameCaller name
Exceptions
DBErrorIf an error occurs, {
See also
query}
Exceptions
ExceptionIf the callback runs immediately and an error occurs in it
Since
1.28

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2255 of file Database.php.

◆ open()

Wikimedia\Rdbms\Database::open ( $server,
$user,
$password,
$db,
$schema,
$tablePrefix )
abstractprotected

Open a new connection to the database (closing any existing one)

Parameters
string | null$serverServer host/address and optional port {
See also
connectionParams}
Parameters
string | null$userUser name {
See also
connectionParams}
Parameters
string | null$passwordUser password {
See also
connectionParams}
Parameters
string | null$dbDatabase name
string | null$schemaDatabase schema name
string$tablePrefix
Exceptions
DBConnectionError

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Referenced by Wikimedia\Rdbms\Database\doInitConnection().

◆ pendingWriteAndCallbackCallers()

Wikimedia\Rdbms\Database::pendingWriteAndCallbackCallers ( )

Definition at line 3598 of file Database.php.

◆ pendingWriteCallers()

Wikimedia\Rdbms\Database::pendingWriteCallers ( )

Get the list of method names that did write queries for this transaction.

Returns
array
Since
1.27

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3591 of file Database.php.

◆ pendingWriteQueryDuration()

Wikimedia\Rdbms\Database::pendingWriteQueryDuration ( $type = self::ESTIMATE_TOTAL)

Get the time spend running write queries for this transaction.

High values could be due to scanning, updates, locking, and such.

Parameters
string$typeIDatabase::ESTIMATE_* constant [default: ESTIMATE_ALL]
Returns
float|false Returns false if not transaction is active
Since
1.26

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3587 of file Database.php.

References $type.

◆ ping()

Wikimedia\Rdbms\Database::ping ( )

Ping the server and try to reconnect if it there is no connection.

Returns
bool Success or failure

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 2862 of file Database.php.

References $res.

◆ primaryPosWait()

Wikimedia\Rdbms\Database::primaryPosWait ( DBPrimaryPos $pos,
$timeout )

Wait for the replica server to catch up to a given primary server position.

Note that this does not start any new transactions.

Callers might want to flush any existing transaction before invoking this method. Upon success, this assures that replica server queries will reflect all changes up to the given position, without interference from prior REPEATABLE-READ snapshots.

Parameters
DBPrimaryPos$pos
int$timeoutThe maximum number of seconds to wait for synchronisation
Returns
int|null Zero if the replica DB server was past that position already, greater than zero if we waited for some period of time, less than zero if it timed out, and null on error
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.37

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 3815 of file Database.php.

◆ query()

Wikimedia\Rdbms\Database::query ( $sql,
$fname = __METHOD__,
$flags = 0 )

Run an SQL query statement and return the result.

If a connection loss is detected, then an attempt to reconnect will be made. For queries that involve no larger transactions or locks, they will be re-issued for convenience, provided the connection was re-established.

In new code, the query wrappers select(), insert(), update(), delete(), etc. should be used where possible, since they give much better DBMS independence and automatically quote or validate user input in a variety of contexts. This function is generally only useful for queries which are explicitly DBMS-dependent and are unsupported by the query wrappers, such as CREATE TABLE.

However, the query wrappers themselves should call this function.

Callers should avoid the use of statements like BEGIN, COMMIT, and ROLLBACK. Methods like startAtomic(), endAtomic(), and cancelAtomic() can be used instead.

Parameters
string$sqlSingle-statement SQL query
string$fnameCaller name; used for profiling/SHOW PROCESSLIST comments
int$flagsBit field of IDatabase::QUERY_* constants.
Returns
bool|IResultWrapper True for a successful write query, IResultWrapper object for a successful read query, or false on failure if QUERY_SILENCE_ERRORS is set.
Exceptions
DBQueryErrorIf the query is issued, fails, and QUERY_SILENCE_ERRORS is not set.
DBExpectedErrorIf the query is not, and cannot, be issued yet (non-DBQueryError)
DBErrorIf the query is inherently not allowed (non-DBExpectedError)

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 838 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\doLock(), Wikimedia\Rdbms\DatabaseMysqlBase\doLockIsFree(), Wikimedia\Rdbms\DatabaseMysqlBase\doReplace(), Wikimedia\Rdbms\DatabaseMysqlBase\doUnlock(), Wikimedia\Rdbms\DatabaseMysqlBase\doUpsert(), Wikimedia\Rdbms\DatabaseMysqlBase\duplicateTableStructure(), Wikimedia\Rdbms\DatabaseMysqlBase\fieldInfo(), Wikimedia\Rdbms\PostgresField\fromText(), Wikimedia\Rdbms\DatabaseMysqlBase\indexInfo(), Wikimedia\Rdbms\DatabaseMysqlBase\listTables(), Wikimedia\Rdbms\DatabaseMysqlBase\listViews(), Wikimedia\Rdbms\DatabasePostgres\open(), Wikimedia\Rdbms\DatabaseSqlite\open(), Wikimedia\Rdbms\DatabaseMysqlBase\serverIsReadOnly(), Wikimedia\Rdbms\DatabaseMysqlBase\setSessionOptions(), and Wikimedia\Rdbms\DatabaseMysqlBase\tableExists().

◆ queryMulti()

Wikimedia\Rdbms\Database::queryMulti ( array $sqls,
string $fname = __METHOD__,
int $flags = 0,
?string $summarySql = null )

Run a batch of SQL query statements and return the results.

If any statement results in an error, subsequent statements will not be attempted.

Callers should avoid the use of statements like BEGIN, COMMIT, and ROLLBACK. Methods like startAtomic(), endAtomic(), and cancelAtomic() can be used instead.

See also
IDatabase::query()
Parameters
string[]$sqlsMap of (statement ID => SQL statement)
string$fnameName of the calling function
int$flagsBit field of IDatabase::QUERY_* constants
string | null$summarySqlVirtual SQL for profiling (e.g. "UPSERT INTO TABLE 'x'")
Returns
array<string,QueryStatus> Ordered map of (statement ID => QueryStatus)
Exceptions
DBQueryErrorIf a query is issued, fails, and QUERY_SILENCE_ERRORS is not set.
DBExpectedErrorIf a query is not, and cannot, be issued yet (non-DBQueryError)
Since
1.39

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 861 of file Database.php.

◆ registerTempWrites()

Wikimedia\Rdbms\Database::registerTempWrites ( $ret,
array $changes )
protected
Parameters
IResultWrapper | bool$ret
array[]$changesList of change n-tuples with from getTempTableWrites()

Definition at line 792 of file Database.php.

◆ replace()

Wikimedia\Rdbms\Database::replace ( $table,
$uniqueKeys,
$rows,
$fname = __METHOD__ )

Insert row(s) into a table, in the provided order, while deleting conflicting rows.

Conflicts are determined by the provided unique indexes. Note that it is possible for the provided rows to conflict even among themselves; it is preferable for the caller to de-duplicate such input beforehand.

Note some important implications of the deletion semantics:

  • If the table has an AUTOINCREMENT column and $rows omit that column, then any conflicting existing rows will be replaced with newer having higher values for that column, even if nothing else changed.
  • There might be worse contention than upsert() due to the use of gap-locking. This does not apply to RDBMS types that use predicate locking nor those that just lock the whole table or databases anyway.

This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.

Parameters
string$tableThe table name
string | string[] | string[][]$uniqueKeysColumn name or non-empty list of column name lists that define all applicable unique keys on the table. There must only be one such key. Each unique key on the table is "applicable" unless either:
  • It involves an AUTOINCREMENT column for which no values are assigned in $rows
  • It involves a UUID column for which newly generated UUIDs are assigned in $rows
array | array[]$rowsRow(s) to insert, in the form of either:
  • A string-keyed map of (column name => value) defining a new row. Values are treated as literals and quoted appropriately; null is interpreted as NULL. Columns belonging to a key in $uniqueKeys must be defined here and non-null.
  • An integer-keyed list of such string-keyed maps, defining a list of new rows. The keys in each map must be identical to each other and in the same order. The rows must not collide with each other.
string$fnameCalling function name (use METHOD) for logs/profiling
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 1836 of file Database.php.

◆ replaceLostConnection()

Wikimedia\Rdbms\Database::replaceLostConnection ( $lastErrno,
$fname )
protected

Close any existing (dead) database connection and open a new connection.

Parameters
int | null$lastErrno
string$fname
Returns
bool True if new connection is opened successfully, false if error

Definition at line 2891 of file Database.php.

◆ reportQueryError()

Wikimedia\Rdbms\Database::reportQueryError ( $error,
$errno,
$sql,
$fname,
$ignore = false )

Report a query error.

If $ignore is set, emit a DEBUG level log entry and continue, otherwise, emit an ERROR level log entry and throw an exception.

Parameters
string$error
int | string$errno
string$sql
string$fname
bool$ignoreWhether to just log an error rather than throw an exception
Exceptions
DBQueryError

Definition at line 1475 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\doFlushSession(), Wikimedia\Rdbms\DatabaseMysqlBase\doSelectDomain(), and Wikimedia\Rdbms\DatabaseMysqlBase\open().

◆ restoreErrorHandler()

Wikimedia\Rdbms\Database::restoreErrorHandler ( )
protected

Restore the previous error handler and return the last PHP error for this DB.

Returns
string|false

Definition at line 534 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\open(), and Wikimedia\Rdbms\DatabasePostgres\open().

◆ restoreFlags()

Wikimedia\Rdbms\Database::restoreFlags ( $state = self::RESTORE_PRIOR)

Restore the flags to their prior state before the last setFlag/clearFlag call.

Parameters
string$stateIDatabase::RESTORE_* constant. [default: RESTORE_PRIOR]
Since
1.28

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 3549 of file Database.php.

◆ rollback()

Wikimedia\Rdbms\Database::rollback ( $fname = __METHOD__,
$flush = self::FLUSHING_ONE )
final

Rollback a transaction previously started using begin()

Only call this from code with outer transaction scope. See https://www.mediawiki.org/wiki/Database_transactions for details. Nesting of transactions is not supported. If a serious unexpected error occurs, throwing an Exception is preferable, using a pre-installed error handler to trigger rollback (in any case, failure to issue COMMIT will cause rollback server-side).

Query, connection, and onTransaction* callback errors will be suppressed and logged.

Parameters
string$fnameCalling function name
string$flushFlush flag, set to a situationally valid IDatabase::FLUSHING_* constant to disable warnings about explicitly rolling back implicit transactions. This will silently break any ongoing explicit transaction. Only set the flush flag if you are sure that it is safe to ignore these warnings in your context.
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.23 Added $flush parameter

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2717 of file Database.php.

◆ runOnTransactionIdleCallbacks()

Wikimedia\Rdbms\Database::runOnTransactionIdleCallbacks ( $trigger,
array & $errors = [] )

Consume and run any "on transaction idle/resolution" callbacks.

Access: internal
This method should not be used outside of Database/LoadBalancer
Since
1.20
Parameters
int$triggerIDatabase::TRIGGER_* constant
DBError[]&$errorsDB exceptions caught [returned]
Returns
int Number of callbacks attempted
Exceptions
DBUnexpectedError
ThrowableAny non-DBError exception thrown by a callback

Definition at line 2338 of file Database.php.

◆ runOnTransactionPreCommitCallbacks()

Wikimedia\Rdbms\Database::runOnTransactionPreCommitCallbacks ( )

Definition at line 3605 of file Database.php.

◆ runTransactionListenerCallbacks()

Wikimedia\Rdbms\Database::runTransactionListenerCallbacks ( $trigger,
array & $errors = [] )

Actually run any "transaction listener" callbacks.

Access: internal
This method should not be used outside of Database/LoadBalancer
Since
1.20
Parameters
int$triggerIDatabase::TRIGGER_* constant
DBError[]&$errorsDB exceptions caught [returned]
Exceptions
ThrowableAny non-DBError exception thrown by a callback

Definition at line 2393 of file Database.php.

◆ select()

Wikimedia\Rdbms\Database::select ( $table,
$vars,
$conds = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Execute a SELECT query constructed using the various parameters provided.

New callers should use newSelectQueryBuilder with SelectQueryBuilder::fetchResultSet instead, which is more readable and less error-prone.

Parameters
string | array$tableTable name(s)

May be either an array of table names, or a single string holding a table name. If an array is given, table aliases can be specified, for example:

[ 'a' => 'user' ]

This includes the user table in the query, with the alias "a" available for use in field names (e.g. a.user_name).

A derived table, defined by the result of selectSQLText(), requires an alias key and a Subquery instance value which wraps the SQL query, for example:

[ 'c' => new Subquery( 'SELECT ...' ) ]

Joins using parentheses for grouping (since MediaWiki 1.31) may be constructed using nested arrays. For example,

[ 'tableA', 'nestedB' => [ 'tableB', 'b2' => 'tableB2' ] ]

along with $join_conds like

[ 'b2' => [ 'JOIN', 'b_id = b2_id' ], 'nestedB' => [ 'LEFT JOIN', 'b_a = a_id' ] ]

will produce SQL something like

FROM tableA LEFT JOIN (tableB JOIN tableB2 AS b2 ON (b_id = b2_id)) ON (b_a = a_id)

All of the table names given here are automatically run through Database::tableName(), which causes the table prefix (if any) to be added, and various other table name mappings to be performed.

Do not use untrusted user input as a table name. Alias names should not have characters outside of the Basic multilingual plane.

Parameters
string | array$varsField name(s)

May be either a field name or an array of field names. The field names can be complete fragments of SQL, for direct inclusion into the SELECT query. If an array is given, field aliases can be specified, for example:

[ 'maxrev' => 'MAX(rev_id)' ]

This includes an expression with the alias "maxrev" in the query.

If an expression is given, care must be taken to ensure that it is DBMS-independent.

Untrusted user input must not be passed to this parameter.

Parameters
string | array$conds

May be either a string containing a single condition, or an array of conditions. If an array is given, the conditions constructed from each element are combined with AND.

Array elements may take one of two forms:

  • Elements with a numeric key are interpreted as raw SQL fragments.
  • Elements with a string key are interpreted as equality conditions, where the key is the field name.
    • If the value of such an array element is a scalar (such as a string), it will be treated as data and thus quoted appropriately. If it is null, an IS NULL clause will be added.
    • If the value is an array, an IN (...) clause will be constructed from its non-null elements, and an IS NULL clause will be added if null is present, such that the field may match any of the elements in the array. The non-null elements will be quoted.

Note that expressions are often DBMS-dependent in their syntax. DBMS-independent wrappers are provided for constructing several types of expression commonly used in condition queries. See:

  • IDatabase::buildLike()
  • IDatabase::conditional()

Untrusted user input is safe in the values of string keys, however untrusted input must not be used in the array key names or in the values of numeric keys. Escaping of untrusted input used in values of numeric keys should be done via IDatabase::addQuotes()

Use an empty array, string, or IDatabase::ALL_ROWS to select all rows.

You can put simple join conditions here, but this is strongly discouraged. Instead of

// $conds...
'rev_actor = actor_id',

use (see below for $join_conds):

// $join_conds...
'actor' => [ 'JOIN', 'rev_actor = actor_id' ],
Parameters
string$fnameCaller function name
string | array$optionsQuery options

Optional: Array of query options. Boolean options are specified by including them in the array as a string value with a numeric key, for example:

[ 'FOR UPDATE' ]

The supported options are:

  • OFFSET: Skip this many rows at the start of the result set. OFFSET with LIMIT can theoretically be used for paging through a result set, but this is discouraged for performance reasons.
  • LIMIT: Integer: return at most this many rows. The rows are sorted and then the first rows are taken until the limit is reached. LIMIT is applied to a result set after OFFSET.
  • LOCK IN SHARE MODE: Boolean: lock the returned rows so that they can't be changed until the next COMMIT. Cannot be used with aggregate functions (COUNT, MAX, etc., but also DISTINCT).
  • FOR UPDATE: Boolean: lock the returned rows so that they can't be changed nor read with LOCK IN SHARE MODE until the next COMMIT. Cannot be used with aggregate functions (COUNT, MAX, etc., but also DISTINCT).
  • DISTINCT: Boolean: return only unique result rows.
  • GROUP BY: May be either an SQL fragment string naming a field or expression to group by, or an array of such SQL fragments.
  • HAVING: May be either an string containing a HAVING clause or an array of conditions building the HAVING clause. If an array is given, the conditions constructed from each element are combined with AND.
  • ORDER BY: May be either an SQL fragment giving a field name or expression to order by, or an array of such SQL fragments.
  • USE INDEX: This may be either a string giving the index name to use for the query, or an array. If it is an associative array, each key gives the table name (or alias), each value gives the index name to use for that table. All strings are SQL fragments and so should be validated by the caller.
  • IGNORE INDEX: This may be either be a string giving an index name to ignore for the query, or an array. If it is an associative array, each key gives the table name (or alias), each value gives the index name to ignore for that table. All strings are SQL fragments and so should be validated by the caller.
  • EXPLAIN: In MySQL, this causes an EXPLAIN SELECT query to be run, instead of SELECT.
  • MAX_EXECUTION_TIME: (only in MySQL/MariaDB) maximum allowed time to run the query in milliseconds (if database supports it).

And also the following boolean MySQL extensions, see the MySQL manual for documentation:

  • STRAIGHT_JOIN
  • SQL_BIG_RESULT
  • SQL_BUFFER_RESULT
  • SQL_SMALL_RESULT
  • SQL_CALC_FOUND_ROWS
Parameters
string | array$join_condsJoin conditions

Optional associative array of table-specific join conditions. Simple conditions can also be specified in the regular $conds, but this is strongly discouraged in favor of the more explicit syntax here.

The key of the array contains the table name or alias. The value is an array with two elements, numbered 0 and 1. The first gives the type of join, the second is the same as the $conds parameter. Thus it can be an SQL fragment, or an array where the string keys are equality and the numeric keys are SQL fragments all AND'd together. For example:

[ 'page' => [ 'LEFT JOIN', 'page_latest=rev_id' ] ]

Returns
IResultWrapper Resulting rows
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1618 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\estimateRowCount().

◆ selectDomain()

Wikimedia\Rdbms\Database::selectDomain ( $domain)
final

Set the current domain (database, schema, and table prefix)

This will throw an error for some database types if the database is unspecified

This should only be called by a load balancer or if the handle is not attached to one

Parameters
string | DatabaseDomain$domain
Exceptions
DBConnectionErrorIf databasesAreIndependent() is true and connection change fails
DBErrorOn query error, if domain changes are disallowed, or the domain is invalid
Since
1.32

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1776 of file Database.php.

Referenced by DatabaseInstaller\selectDatabase().

◆ selectField()

Wikimedia\Rdbms\Database::selectField ( $table,
$var,
$cond = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

A SELECT wrapper which returns a single field from a single result row.

If no result rows are returned from the query, false is returned.

New callers should use newSelectQueryBuilder with SelectQueryBuilder::fetchField instead, which is more readable and less error-prone.

Parameters
string | array$tableTable name. {
See also
select} for details.
Parameters
string | array$varThe field name to select. This must be a valid SQL fragment: do not use unvalidated user input. Can be an array, but must contain exactly 1 element then. {
See also
select} for details.
Parameters
string | array$condThe condition array. {
See also
select} for details.
Parameters
string$fnameThe function name of the caller.
string | array$optionsThe query options. {
See also
select} for details.
Parameters
string | array$join_condsThe query join conditions. {
See also
select} for details.
Returns
mixed|false The value from the field, or false if nothing was found
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1570 of file Database.php.

References $res.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\getServerVersion().

◆ selectFieldValues()

Wikimedia\Rdbms\Database::selectFieldValues ( $table,
$var,
$cond = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

A SELECT wrapper which returns a list of single field values from result rows.

If no result rows are returned from the query, an empty array is returned.

New callers should use newSelectQueryBuilder with SelectQueryBuilder::fetchFieldValues instead, which is more readable and less error-prone.

Parameters
string | array$tableTable name. {
See also
select} for details.
Parameters
string$varThe field name to select. This must be a valid SQL fragment: do not use unvalidated user input.
string | array$condThe condition array. {
See also
select} for details.
Parameters
string$fnameThe function name of the caller.
string | array$optionsThe query options. {
See also
select} for details.
Parameters
string | array$join_condsThe query join conditions. {
See also
select} for details.
Returns
array The values from the field in the order they were returned from the DB
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.25

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1595 of file Database.php.

◆ selectRow()

Wikimedia\Rdbms\Database::selectRow ( $table,
$vars,
$conds,
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Wrapper to IDatabase::select() that only fetches one row (via LIMIT)

If the query returns no rows, false is returned.

This method is convenient for fetching a row based on a unique key condition.

New callers should use newSelectQueryBuilder with SelectQueryBuilder::fetchRow instead, which is more readable and less error-prone.

Parameters
string | array$tableTable name
string | array$varsField names
string | array$condsConditions
string$fnameCaller function name
string | array$optionsQuery options
array | string$join_condsJoin conditions
Returns
stdClass|false
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1632 of file Database.php.

References $res.

◆ selectRowCount()

Wikimedia\Rdbms\Database::selectRowCount ( $tables,
$var = ' *',
$conds = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Get the number of rows in dataset.

This is useful when trying to do COUNT(*) but with a LIMIT for performance.

Takes the same arguments as IDatabase::select().

New callers should use newSelectQueryBuilder with SelectQueryBuilder::fetchRowCount instead, which is more readable and less error-prone.

Since
1.27 Added $join_conds parameter
Parameters
string | string[]$tablesTable name(s)
string$varColumn for which NULL values are not counted [default "*"]
array | string$condsFilters on the table
string$fnameFunction name for profiling
array$optionsOptions for select
array$join_condsJoin conditions (since 1.27)
Returns
int Row count
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 1671 of file Database.php.

References $res.

◆ selectSQLText()

Wikimedia\Rdbms\Database::selectSQLText ( $table,
$vars,
$conds = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Take the same arguments as IDatabase::select() and return the SQL it would use.

This can be useful for making UNION queries, where the SQL text of each query is needed. In general, however, callers outside of Database classes should just use select().

See also
IDatabase::select()
Parameters
string | array$tableTable name(s)
string | array$varsField names
string | array$condsConditions
string$fnameCaller function name
string | array$optionsQuery options
string | array$join_condsJoin conditions
Returns
string SQL query string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase.

Definition at line 3625 of file Database.php.

◆ serverIsReadOnly()

Wikimedia\Rdbms\Database::serverIsReadOnly ( )

Returns
bool Whether the DB server is marked as read-only server-side
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.28

Stability: stable
to override

Implements Wikimedia\Rdbms\IDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2251 of file Database.php.

◆ sessionLocksPending()

Wikimedia\Rdbms\Database::sessionLocksPending ( )
Returns
bool
Since
1.39
Access: internal
For use by Database/LoadBalancer only

Definition at line 473 of file Database.php.

◆ setFlag()

Wikimedia\Rdbms\Database::setFlag ( $flag,
$remember = self::REMEMBER_NOTHING )

Set a flag for this connection.

Parameters
int$flagOne of (IDatabase::DBO_DEBUG, IDatabase::DBO_TRX)
string$rememberIDatabase::REMEMBER_* constant [default: REMEMBER_NOTHING]

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 3541 of file Database.php.

◆ setIndexAliases()

Wikimedia\Rdbms\Database::setIndexAliases ( array $aliases)

Convert certain index names to alternative names before querying the DB.

Note that this applies to indexes regardless of the table they belong to.

This can be employed when an index was renamed X => Y in code, but the new Y-named indexes were not yet built on all DBs. After all the Y-named ones are added by the DBA, the aliases can be removed, and then the old X-named indexes dropped.

Parameters
string[]$aliases
Since
1.31 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3787 of file Database.php.

◆ setLBInfo()

Wikimedia\Rdbms\Database::setLBInfo ( $nameOrArray,
$value = null )

Set the entire array or a particular key of the managing load balancer info array.

Keys matching the IDatabase::LB_* constants are also used internally by subclasses

Parameters
array | string$nameOrArrayThe new array or the name of a key to set
array | mixed | null$valueIf $nameOrArray is a string, the new key value (null to unset)

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 445 of file Database.php.

Referenced by Wikimedia\Rdbms\LoadBalancerSingle\__construct().

◆ setLogger()

Wikimedia\Rdbms\Database::setLogger ( LoggerInterface $logger)

Set the PSR-3 logger interface to use.

Parameters
LoggerInterface$logger

Definition at line 371 of file Database.php.

◆ setSchemaVars()

Wikimedia\Rdbms\Database::setSchemaVars ( $vars)

Set schema variables to be used when streaming commands from SQL files or stdin.

Variables appear as SQL comments and are substituted by their corresponding values

Parameters
array | null$varsMap of (variable => value) or null to use the defaults

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3808 of file Database.php.

◆ setSessionOptions()

Wikimedia\Rdbms\Database::setSessionOptions ( array $options)

Override database's default behavior.$options include: 'connTimeout' : Set the connection timeout value in seconds. May be useful for very long batch queries such as full-wiki dumps, where a single query reads out over hours or days.

Parameters
array$options
Returns
void
Exceptions
DBErrorIf an error occurs, {
See also
query}

Stability: stable
to override

Implements Wikimedia\Rdbms\IDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase.

Definition at line 3002 of file Database.php.

◆ setTableAliases()

Wikimedia\Rdbms\Database::setTableAliases ( array $aliases)

Make certain table names use their own database, schema, and table prefix when passed into SQL queries pre-escaped and without a qualified database name.

For example, "user" can be converted to "myschema.mydbname.user" for convenience. Appearances like user, somedb.user, somedb.someschema.user will used literally.

Calling this twice will completely clear any old table aliases. Also, note that callers are responsible for making sure the schemas and databases actually exist.

Parameters
array[]$aliasesMap of (table => (dbname, schema, prefix) map)
Since
1.28 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Reimplemented in Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 3779 of file Database.php.

◆ setTransactionListener()

Wikimedia\Rdbms\Database::setTransactionListener ( $name,
callable $callback = null )
final

Run a callback after each time any transaction commits or rolls back.

The callback takes two arguments:

  • IDatabase::TRIGGER_COMMIT or IDatabase::TRIGGER_ROLLBACK
  • This IDatabase object Callbacks must commit any transactions that they begin.

Registering a callback here will not affect writesOrCallbacks() pending.

Since callbacks from this or onTransactionCommitOrIdle() can start and end transactions, a single call to IDatabase::commit might trigger multiple runs of the listener callbacks.

Parameters
string$nameCallback name
callable | null$callbackUse null to unset a listener
Since
1.28

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2310 of file Database.php.

◆ setTransactionManager()

Wikimedia\Rdbms\Database::setTransactionManager ( TransactionManager $transactionManager)
Access: internal
Only for tests and highly discouraged
Parameters
TransactionManager$transactionManager

Definition at line 2764 of file Database.php.

◆ setTrxEndCallbackSuppression()

Wikimedia\Rdbms\Database::setTrxEndCallbackSuppression ( $suppress)
final

Whether to disable running of post-COMMIT/ROLLBACK callbacks.

Access: internal
This method should not be used outside of Database/LoadBalancer
Since
1.28
Parameters
bool$suppress

Definition at line 2322 of file Database.php.

◆ sourceFile()

Wikimedia\Rdbms\Database::sourceFile ( $filename,
callable $lineCallback = null,
callable $resultCallback = null,
$fname = false,
callable $inputCallback = null )

Read and execute SQL commands from a file.

Returns true on success, error string or exception on failure (depending on object's error ignore settings).

Parameters
string$filenameFile name to open
callable | null$lineCallbackOptional function called before reading each line
callable | null$resultCallbackOptional function called for each MySQL result
string | false$fnameCalling function name or false if name should be generated dynamically using $filename
callable | null$inputCallbackOptional function called for each complete line sent
Returns
bool|string
Exceptions
Exception

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 3005 of file Database.php.

◆ sourceStream()

Wikimedia\Rdbms\Database::sourceStream ( $fp,
callable $lineCallback = null,
callable $resultCallback = null,
$fname = __METHOD__,
callable $inputCallback = null )

Read and execute commands from an open file handle.

Returns true on success, error string or exception on failure (depending on object's error ignore settings).

Parameters
resource$fpFile handle
callable | null$lineCallbackOptional function called before reading each query
callable | null$resultCallbackOptional function called for each MySQL result
string$fnameCalling function name
callable | null$inputCallbackOptional function called for each complete query sent
Returns
bool|string

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 3037 of file Database.php.

References $res.

◆ startAtomic()

Wikimedia\Rdbms\Database::startAtomic ( $fname = __METHOD__,
$cancelable = self::ATOMIC_NOT_CANCELABLE )
final

Begin an atomic section of SQL statements.

Start an implicit transaction if no transaction is already active, set a savepoint (if $cancelable is ATOMIC_CANCELABLE), and track the given section name to enforce that the transaction is not committed prematurely. The end of the section must be signified exactly once, either by endAtomic() or cancelAtomic(). Sections can have have layers of inner sections (sub-sections), but all sections must be ended in order of innermost to outermost. Transactions cannot be started or committed until all atomic sections are closed.

ATOMIC_CANCELABLE is useful when the caller needs to handle specific failure cases by discarding the section's writes. This should not be used for failures when:

  • upsert() could easily be used instead
  • insert() with IGNORE could easily be used instead
  • select() with FOR UPDATE could be checked before issuing writes instead
  • The failure is from code that runs after the first write but doesn't need to
  • The failures are from contention solvable via onTransactionPreCommitOrIdle()
  • The failures are deadlocks; the RDBMs usually discard the whole transaction
Note
callers must use additional measures for situations involving two or more (peer) transactions (e.g. updating two database servers at once). The transaction and savepoint logic of this method only applies to this specific IDatabase instance.

Example usage:

// Start a transaction if there isn't one already
$dbw->startAtomic( __METHOD__ );
// Serialize these thread table updates
$dbw->select( 'thread', '1', [ 'td_id' => $tid ], __METHOD__, 'FOR UPDATE' );
// Add a new comment for the thread
$dbw->insert( 'comment', $row, __METHOD__ );
$cid = $db->insertId();
// Update thread reference to last comment
$dbw->update( 'thread', [ 'td_latest' => $cid ], [ 'td_id' => $tid ], __METHOD__ );
// Demark the end of this conceptual unit of updates
$dbw->endAtomic( __METHOD__ );

Example usage (atomic changes that might have to be discarded):

// Start a transaction if there isn't one already
$sectionId = $dbw->startAtomic( __METHOD__, $dbw::ATOMIC_CANCELABLE );
// Create new record metadata row
$dbw->insert( 'records', $row, __METHOD__ );
// Figure out where to store the data based on the new row's ID
$path = $recordDirectory . '/' . $dbw->insertId();
// Write the record data to the storage system
$status = $fileBackend->create( [ 'dst' => $path, 'content' => $data ] );
if ( $status->isOK() ) {
// Try to cleanup files orphaned by transaction rollback
$dbw->onTransactionResolution(
function ( $type ) use ( $fileBackend, $path ) {
if ( $type === IDatabase::TRIGGER_ROLLBACK ) {
$fileBackend->delete( [ 'src' => $path ] );
}
},
__METHOD__
);
// Demark the end of this conceptual unit of updates
$dbw->endAtomic( __METHOD__ );
} else {
// Discard these writes from the transaction (preserving prior writes)
$dbw->cancelAtomic( __METHOD__, $sectionId );
}
Since
1.23
Parameters
string$fname
string$cancelablePass self::ATOMIC_CANCELABLE to use a savepoint and enable self::cancelAtomic() for this section.
Returns
AtomicSectionIdentifier section ID token
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 2439 of file Database.php.

◆ streamStatementEnd()

Wikimedia\Rdbms\Database::streamStatementEnd ( & $sql,
& $newLine )

Called by sourceStream() to check if we've reached a statement end.

Stability: stable
to override
Parameters
string&$sqlSQL assembled so far
string&$newLineNew line about to be added to $sql
Returns
bool Whether $newLine contains end of the statement

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DatabasePostgres.

Definition at line 3115 of file Database.php.

◆ strencode()

Wikimedia\Rdbms\Database::strencode ( $s)
abstract

Wrapper for addslashes()

Stability: stable
to override
Parameters
string$sString to be slashed.
Returns
string Slashed string.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

◆ strreplace()

Wikimedia\Rdbms\Database::strreplace ( $orig,
$old,
$new )

Returns a SQL expression for simple string replacement (e.g.

REPLACE() in mysql)

Parameters
string$origColumn to modify
string$oldColumn to seek
string$newColumn to replace with
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3755 of file Database.php.

◆ tableExists()

Wikimedia\Rdbms\Database::tableExists ( $table,
$fname = __METHOD__ )
abstract

Query whether a given table exists.

Parameters
string$table
string$fname
Returns
bool
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DatabaseSqlite.

◆ tableName()

Wikimedia\Rdbms\Database::tableName ( $name,
$format = 'quoted' )

Format a table name ready for use in constructing an SQL query.

This does two important things: it quotes the table names to clean them up, and it adds a table prefix if only given a table name with no quotes.

All functions of this object which require a table name call this function themselves. Pass the canonical name to such functions. This is only needed when calling query() directly.

Note
This function does not sanitize user input. It is not safe to use this function to escape user input.
Parameters
string$nameDatabase table name
string$formatOne of: quoted - Automatically pass the table name through addIdentifierQuotes() so that it can be used in a query. raw - Do not add identifier quotes to the table name
Returns
string Full database name

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3683 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\doReplace(), Wikimedia\Rdbms\DatabaseMysqlBase\doUpsert(), Wikimedia\Rdbms\DatabaseMysqlBase\fieldInfo(), and Wikimedia\Rdbms\DatabaseMysqlBase\indexInfo().

◆ tableNames()

Wikimedia\Rdbms\Database::tableNames ( $tables)

Fetch a number of table names into an associative array.

Much like tableName(), this is only needed when calling query() directly. Prefer calling other methods, or using SelectQueryBuilder.

Theoretical example (which really does not require raw SQL): [ 'user' => $user, 'watchlist' => $watchlist ] = $dbr->tableNames( 'user', 'watchlist' ); $sql = "SELECT wl_namespace, wl_title FROM $watchlist, $user WHERE wl_user=user_id AND wl_user=$nameWithQuotes";

Parameters
string...$tables
Returns
array
Deprecated
since 1.39; if you must format table names, write several calls to tableName or use tableNamesN instead of calling this function.

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3687 of file Database.php.

◆ tableNamesN()

Wikimedia\Rdbms\Database::tableNamesN ( $tables)

Fetch a number of table names into a zero-indexed numerical array.

Much like tableName(), this is only needed when calling query() directly. It is slightly more convenient than tableNames(), but you should still prefer calling other methods, or using SelectQueryBuilder.

Theoretical example (which really does not require raw SQL): [ $user, $watchlist ] = $dbr->tableNamesN( 'user', 'watchlist' ); $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user WHERE wl_user=user_id AND wl_user=$nameWithQuotes";

Parameters
string...$tables
Returns
array

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3691 of file Database.php.

◆ tablePrefix()

Wikimedia\Rdbms\Database::tablePrefix ( $prefix = null)

Get/set the table prefix.

Parameters
string | null$prefixThe table prefix to set, or omitted to leave it unchanged
Returns
string The previous table prefix

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 395 of file Database.php.

Referenced by DatabaseInstaller\selectDatabase().

◆ textFieldSize()

Wikimedia\Rdbms\Database::textFieldSize ( $table,
$field )

Returns the size of a text field, or -1 for "unlimited".

Parameters
string$table
string$field
Returns
int

Stability: stable
to override

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 1999 of file Database.php.

References $res.

◆ timestamp()

Wikimedia\Rdbms\Database::timestamp ( $ts = 0)

Convert a timestamp in one of the formats accepted by ConvertibleTimestamp to the format used for inserting into timestamp fields in this DBMS.

The result is unquoted, and needs to be passed through addQuotes() before it can be included in raw SQL.

Parameters
string | int$ts
Returns
string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3759 of file Database.php.

◆ timestampOrNull()

Wikimedia\Rdbms\Database::timestampOrNull ( $ts = null)

Convert a timestamp in one of the formats accepted by ConvertibleTimestamp to the format used for inserting into timestamp fields in this DBMS.

If NULL is input, it is passed through, allowing NULL values to be inserted into timestamp fields.

The result is unquoted, and needs to be passed through addQuotes() before it can be included in raw SQL.

Parameters
string | int | null$ts
Returns
string|null

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3763 of file Database.php.

◆ truncate()

Wikimedia\Rdbms\Database::truncate ( $tables,
$fname = __METHOD__ )

Delete all data in a table(s) and reset any sequences owned by that table(s)

Parameters
string | string[]$tables
string$fname
Exceptions
DBErrorIf an error occurs
Since
1.35

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 3276 of file Database.php.

◆ trxLevel()

Wikimedia\Rdbms\Database::trxLevel ( )
final

Gets the current transaction level.

Historically, transactions were allowed to be "nested". This is no longer supported, so this function really only returns a boolean.

Returns
int The previous value

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3561 of file Database.php.

◆ trxStatus()

Wikimedia\Rdbms\Database::trxStatus ( )

Definition at line 3575 of file Database.php.

◆ trxTimestamp()

Wikimedia\Rdbms\Database::trxTimestamp ( )

Get the UNIX timestamp of the time that the transaction was established.

This can be used to reason about the staleness of SELECT data in REPEATABLE-READ transaction isolation level. Callers can assume that if a view-snapshot isolation is used, then the data read by SQL queries is at least up to date to that point (possibly more up-to-date since the first SELECT defines the snapshot).

Returns
float|null Returns null if there is not active transaction
Since
1.25

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3571 of file Database.php.

◆ unionConditionPermutations()

Wikimedia\Rdbms\Database::unionConditionPermutations ( $table,
$vars,
array $permute_conds,
$extra_conds = '',
$fname = __METHOD__,
$options = [],
$join_conds = [] )

Construct a UNION query for permutations of conditions.

Databases sometimes have trouble with queries that have multiple values for multiple condition parameters combined with limits and ordering. This method constructs queries for the Cartesian product of the conditions and unions them all together.

See also
IDatabase::select()
Parameters
string | array$tableTable name
string | array$varsField names
array$permute_condsConditions for the Cartesian product. Keys are field names, values are arrays of the possible values for that field.
string | array$extra_condsAdditional conditions to include in the query.
string$fnameCaller function name
string | array$optionsQuery options. In addition to the options recognized by IDatabase::select(), the following may be used:
  • NOTALL: Set to use UNION instead of UNION ALL.
  • INNER ORDER BY: If specified and supported, subqueries will use this instead of ORDER BY.
string | array$join_condsJoin conditions
Returns
string SQL query string.
Since
1.30

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3731 of file Database.php.

◆ unionQueries()

Wikimedia\Rdbms\Database::unionQueries ( $sqls,
$all )

Construct a UNION query.

This is used for providing overload point for other DB abstractions not compatible with the MySQL syntax.

Parameters
array$sqlsSQL statements to combine
bool$allEither IDatabase::UNION_ALL or IDatabase::UNION_DISTINCT
Returns
string SQL fragment

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3727 of file Database.php.

◆ unionSupportsOrderAndLimit()

Wikimedia\Rdbms\Database::unionSupportsOrderAndLimit ( )

Determine if the RDBMS supports ORDER BY and LIMIT for separate subqueries within UNION.

Returns
bool

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 3723 of file Database.php.

◆ unlock()

Wikimedia\Rdbms\Database::unlock ( $lockName,
$method )

Release a lock.Named locks are not related to transactions

Parameters
string$lockNameName of lock to release
string$methodName of the calling method
Returns
bool Success
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3202 of file Database.php.

◆ update()

Wikimedia\Rdbms\Database::update ( $table,
$set,
$conds,
$fname = __METHOD__,
$options = [] )

Update all rows in a table that match a given condition.

This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.

Parameters
string$tableTable name
array$setCombination map/list where each string-keyed entry maps a column to a literal assigned value and each integer-keyed value is a SQL expression in the format of a column assignment within UPDATE...SET. The (column => value) entries are convenient due to automatic value quoting and conversion of null to NULL. The SQL assignment format is useful for updates like "column = column + X". All assignments have no defined execution order, so they should not depend on each other. Do not modify AUTOINCREMENT or UUID columns in assignments.
array | string$condsCondition in the format of IDatabase::select() conditions. In order to prevent possible performance or replication issues or damaging a data accidentally, an empty condition for 'update' queries isn't allowed. IDatabase::ALL_ROWS should be passed explicitly in order to update all rows.
string$fnameCalling function name (use METHOD) for logs/profiling
string | array$optionsCombination map/list where each string-keyed entry maps a non-boolean option to the option parameters and each integer-keyed value is the name of a boolean option. Supported options are:
  • IGNORE: Boolean: skip update of rows that would cause unique key conflicts. IDatabase::affectedRows() can be used to determine how many rows were updated.
Returns
bool Return true if no exception was thrown (deprecated since 1.33)
Exceptions
DBErrorIf an error occurs, {
See also
query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 1761 of file Database.php.

◆ upsert()

Wikimedia\Rdbms\Database::upsert ( $table,
array $rows,
$uniqueKeys,
array $set,
$fname = __METHOD__ )

Upsert row(s) into a table, in the provided order, while updating conflicting rows.

Conflicts are determined by the provided unique indexes. Note that it is possible for the provided rows to conflict even among themselves; it is preferable for the caller to de-duplicate such input beforehand.

This operation will be seen by affectedRows()/insertId() as one query statement, regardless of how many statements are actually sent by the class implementation.

See also
IDatabase::buildExcludedValue()
Parameters
string$tableTable name
array | array[]$rowsRow(s) to insert, in the form of either:
  • A string-keyed map of (column name => value) defining a new row. Values are treated as literals and quoted appropriately; null is interpreted as NULL. Columns belonging to a key in $uniqueKeys must be defined here and non-null.
  • An integer-keyed list of such string-keyed maps, defining a list of new rows. The keys in each map must be identical to each other and in the same order. The rows must not collide with each other.
string | string[] | string[][]$uniqueKeysColumn name or non-empty list of column name lists that define all applicable unique keys on the table. There must only be one such key. Each unique key on the table is "applicable" unless either:
  • It involves an AUTOINCREMENT column for which no values are assigned in $rows
  • It involves a UUID column for which newly generated UUIDs are assigned in $rows
array$setCombination map/list where each string-keyed entry maps a column to a literal assigned value and each integer-keyed value is a SQL assignment expression of the form "<unquoted alphanumeric column> = <SQL expression>". The (column => value) entries are convenient due to automatic value quoting and conversion of null to NULL. The SQL assignment entries are useful for updates like "column = column + X". All of the assignments have no defined execution order, so callers should make sure that they not depend on each other. Do not modify AUTOINCREMENT or UUID columns in assignments, even if they are just "secondary" unique keys. For multi-row upserts, use buildExcludedValue() to reference the value of a column from the corresponding row in $rows that conflicts with the current row.
string$fnameCalling function name (use METHOD) for logs/profiling
Returns
bool Return true if no exception was thrown (deprecated since 1.33)
Exceptions
DBErrorIf an error occurs, {
See also
query}
Since
1.22

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 1879 of file Database.php.

◆ wasConnectionLoss()

Wikimedia\Rdbms\Database::wasConnectionLoss ( )

Determines if the last query error was due to a dropped connection.Note that during a connection loss, the prior transaction will have been lost

Returns
bool
Since
1.31

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 2203 of file Database.php.

◆ wasDeadlock()

Wikimedia\Rdbms\Database::wasDeadlock ( )

Determines if the last failure was due to a deadlock.Note that during a deadlock, the prior transaction will have been lost

Returns
bool

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, Wikimedia\Rdbms\DatabasePostgres, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2187 of file Database.php.

◆ wasErrorReissuable()

Wikimedia\Rdbms\Database::wasErrorReissuable ( )

Determines if the last query error was due to something outside of the query itself.

Note that the transaction may have been lost, discarding prior writes and results

Returns
bool
Deprecated
Since 1.40

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 2215 of file Database.php.

◆ wasLockTimeout()

Wikimedia\Rdbms\Database::wasLockTimeout ( )

Determines if the last failure was due to a lock timeout.Note that during a lock wait timeout, the prior transaction will have been lost

Returns
bool

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DatabasePostgres.

Definition at line 2195 of file Database.php.

◆ wasReadOnlyError()

Wikimedia\Rdbms\Database::wasReadOnlyError ( )

Determines if the last failure was due to the database being read-only.

Returns
bool

Stability: stable
to override

Implements Wikimedia\Rdbms\IReadableDatabase.

Reimplemented in Wikimedia\Rdbms\DatabaseMysqlBase, and Wikimedia\Rdbms\DatabaseSqlite.

Definition at line 2211 of file Database.php.

◆ writesOrCallbacksPending()

Wikimedia\Rdbms\Database::writesOrCallbacksPending ( )

Whether there is a transaction open with either possible write queries or unresolved pre-commit/commit/resolution callbacks pending.

This does not count recurring callbacks, e.g. from setTransactionListener().

Returns
bool

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3583 of file Database.php.

◆ writesPending()

Wikimedia\Rdbms\Database::writesPending ( )
Returns
bool Whether there is a transaction open with possible write queries
Since
1.27

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 3579 of file Database.php.

Member Data Documentation

◆ $affectedRowCount

int null Wikimedia\Rdbms\Database::$affectedRowCount
protected

Affected row count for the last query statement.

Definition at line 103 of file Database.php.

◆ $agent

string Wikimedia\Rdbms\Database::$agent
protected

Agent name for query profiling.

Definition at line 79 of file Database.php.

◆ $cliMode

bool Wikimedia\Rdbms\Database::$cliMode
protected

Whether this PHP instance is for a CLI script.

Definition at line 73 of file Database.php.

◆ $conn

object resource null Wikimedia\Rdbms\Database::$conn
protected

Database connection.

Definition at line 68 of file Database.php.

◆ $connectionParams

array<string,mixed> Wikimedia\Rdbms\Database::$connectionParams
protected

Connection parameters used by initConnection() and open()

Definition at line 81 of file Database.php.

◆ $connectionVariables

string [] int [] float [] Wikimedia\Rdbms\Database::$connectionVariables
protected

SQL variables values to use for all new connections.

Definition at line 83 of file Database.php.

◆ $connectTimeout

int null Wikimedia\Rdbms\Database::$connectTimeout
protected

Maximum seconds to wait on connection attempts.

Definition at line 75 of file Database.php.

◆ $csProvider

CriticalSectionProvider null Wikimedia\Rdbms\Database::$csProvider
protected

Definition at line 49 of file Database.php.

◆ $currentDomain

DatabaseDomain Wikimedia\Rdbms\Database::$currentDomain
protected

Definition at line 62 of file Database.php.

◆ $delimiter

string false Wikimedia\Rdbms\Database::$delimiter = ';'
protected

Current SQL query delimiter.

Definition at line 92 of file Database.php.

◆ $deprecationLogger

callable Wikimedia\Rdbms\Database::$deprecationLogger
protected

Deprecation logging callback.

Definition at line 55 of file Database.php.

◆ $errorLogger

callable Wikimedia\Rdbms\Database::$errorLogger
protected

Error logging callback.

Definition at line 53 of file Database.php.

◆ $flagsHolder

DatabaseFlags Wikimedia\Rdbms\Database::$flagsHolder
protected

Definition at line 64 of file Database.php.

◆ $lastConnectError

string Wikimedia\Rdbms\Database::$lastConnectError = ''
protected

Last error during connection; empty string if none.

Definition at line 106 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\lastError().

◆ $lbInfo

array Wikimedia\Rdbms\Database::$lbInfo = []
protected

Current LoadBalancer tracking information.

Definition at line 90 of file Database.php.

◆ $logger

LoggerInterface Wikimedia\Rdbms\Database::$logger
protected

Definition at line 51 of file Database.php.

◆ $nonNativeInsertSelectBatchSize

int Wikimedia\Rdbms\Database::$nonNativeInsertSelectBatchSize
protected

Row batch size to use for emulated INSERT SELECT queries.

Definition at line 85 of file Database.php.

◆ $platform

SQLPlatform Wikimedia\Rdbms\Database::$platform
protected

Definition at line 179 of file Database.php.

◆ $profiler

callable null Wikimedia\Rdbms\Database::$profiler
protected

Definition at line 57 of file Database.php.

◆ $receiveTimeout

int null Wikimedia\Rdbms\Database::$receiveTimeout
protected

Maximum seconds to wait on receiving query results.

Definition at line 77 of file Database.php.

◆ $replicationReporter

ReplicationReporter Wikimedia\Rdbms\Database::$replicationReporter
protected

Definition at line 182 of file Database.php.

◆ $serverName

string null Wikimedia\Rdbms\Database::$serverName
protected

Readable name or host/IP of the database server.

Definition at line 71 of file Database.php.

◆ $sessionNamedLocks

array<string,array> Wikimedia\Rdbms\Database::$sessionNamedLocks = []
protected

Map of (name => (UNIX time,trx ID)) for current lock() mutexes.

Definition at line 98 of file Database.php.

◆ $sessionTempTables

array<string,array> Wikimedia\Rdbms\Database::$sessionTempTables = []
protected

Map of (name => (type,pristine,trx ID)) for current temp tables.

Definition at line 100 of file Database.php.

◆ $srvCache

BagOStuff Wikimedia\Rdbms\Database::$srvCache
protected

APC cache.

Definition at line 47 of file Database.php.

Referenced by Wikimedia\Rdbms\DatabaseMysqlBase\getServerVersion().

◆ $ssl

bool Wikimedia\Rdbms\Database::$ssl
protected

Whether to use SSL connections.

Definition at line 88 of file Database.php.

◆ CONN_HOST

const Wikimedia\Rdbms\Database::CONN_HOST = 'host'
protected

Hostname or IP address to use on all connections.

Definition at line 166 of file Database.php.

◆ CONN_INITIAL_DB

const Wikimedia\Rdbms\Database::CONN_INITIAL_DB = 'dbname'
protected

Database name to use on initial connection.

Definition at line 172 of file Database.php.

◆ CONN_INITIAL_SCHEMA

const Wikimedia\Rdbms\Database::CONN_INITIAL_SCHEMA = 'schema'
protected

Schema name to use on initial connection.

Definition at line 174 of file Database.php.

◆ CONN_INITIAL_TABLE_PREFIX

const Wikimedia\Rdbms\Database::CONN_INITIAL_TABLE_PREFIX = 'tablePrefix'
protected

Table prefix to use on initial connection.

Definition at line 176 of file Database.php.

◆ CONN_PASSWORD

const Wikimedia\Rdbms\Database::CONN_PASSWORD = 'password'
protected

Database server password to use on all connections.

Definition at line 170 of file Database.php.

◆ CONN_USER

const Wikimedia\Rdbms\Database::CONN_USER = 'user'
protected

Database server username to use on all connections.

Definition at line 168 of file Database.php.

◆ DROPPED_CONN_BLAME_THRESHOLD_SEC

const Wikimedia\Rdbms\Database::DROPPED_CONN_BLAME_THRESHOLD_SEC = 3.0
protected

Assume that queries taking this long to yield connection loss errors are at fault.

Definition at line 150 of file Database.php.

◆ ERR_ABORT_QUERY

const Wikimedia\Rdbms\Database::ERR_ABORT_QUERY = 2
protected

Abort query (no retries) due to a statement rollback (session/transaction intact)

Definition at line 143 of file Database.php.

◆ ERR_ABORT_SESSION

const Wikimedia\Rdbms\Database::ERR_ABORT_SESSION = 8
protected

Abort and reset session due to server-side session-level state loss (locks, temp tables)

Definition at line 147 of file Database.php.

◆ ERR_ABORT_TRX

const Wikimedia\Rdbms\Database::ERR_ABORT_TRX = 4
protected

Abort any current transaction, by rolling it back, due to an error during the query.

Definition at line 145 of file Database.php.

◆ ERR_NONE

const Wikimedia\Rdbms\Database::ERR_NONE = 0
protected

No errors occurred during the query.

Definition at line 139 of file Database.php.

◆ ERR_RETRY_QUERY

const Wikimedia\Rdbms\Database::ERR_RETRY_QUERY = 1
protected

Retry query due to a connection loss detected while sending the query (session intact)

Definition at line 141 of file Database.php.


The documentation for this class was generated from the following file: