Helper class used for automatically re-using IDatabase connections and lazily establishing the actual network connection to a database host. More...

Inherits Stringable, Wikimedia\Rdbms\IMaintainableDatabase, and Wikimedia\Rdbms\IDatabaseForOwner.

Collaboration diagram for Wikimedia\Rdbms\DBConnRef:

[legend]

Public Member Functions
	__call ( $name, array $arguments)

	__construct (ILoadBalancer $lb, $params, $role, &$modcount=0)

	__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.

	affectedRows ()
	Get the number of rows affected by the last query method call.

	andExpr (array $conds)
	See Expression::__construct()

	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=IDatabase::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, $tables, $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 ( $tables, $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.

	databasesAreIndependent ()
	Returns true if DBs are assumed to be on potentially different servers.

	dbSchema ( $schema=null)
	Get/set the db schema.

	decodeBlob ( $b)
	Some DBMSs return a special placeholder object representing blob fields in result objects.

	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.

	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.

	encodeBlob ( $b)
	Some DBMSs have a special format for inserting into blob fields, they don't allow simple quoted strings to be inserted.

	encodeExpiry ( $expiry)
	Encode an expiry time into the DBMS dependent format.

	endAtomic ( $fname=__METHOD__)
	Ends an atomic section of SQL statements.

	ensureConnection ()
	Connect to the database if we are not already connected.

	estimateRowCount ( $tables, $vars=' *', $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
	Estimate the number of rows in dataset.

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

	expr (string $field, string $op, $value)
	See Expression::__construct()

	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.

	fieldInfo ( $table, $field)
	Get information about a field Returns false if the field doesn't exist.

	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 seconds of replication lag on this database server.

	getLBInfo ( $name=null)
	Get properties passed down from the server info array of the load balancer.

	getPrimaryPos ()
	Get the replication position of this primary DB server.

	getProperty ( $name)

	getReferenceRole ()

	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.

	getServerVersion ()
	A string describing the current software version.

	getSessionLagStatus ()
	Get a cached estimate of the seconds of replication lag on this database server, using the estimate obtained at the start of the current transaction if one is active.

	getSoftwareLink ()
	Returns a wikitext style link to the DB's website (e.g.

	getTableAliases ()
	Return current table aliases.

	getType ()
	Get the RDBMS type of the server (e.g.

	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.

	indexUnique ( $table, $index, $fname=__METHOD__)
	Determines if a given index is unique.

	insert ( $table, $rows, $fname=__METHOD__, $options=[])
	Insert row(s) into a table, in the provided order.

	insertId ()
	Get the sequence-based ID assigned by the last query method call.

	insertSelect ( $destTable, $srcTable, $varMap, $conds, $fname=__METHOD__, $insertOptions=[], $selectOptions=[], $selectJoinConds=[])
	INSERT SELECT wrapper.

	isOpen ()

	isReadOnly ()
	Check if this DB server is marked as read-only according to load balancer info.

	lastDoneWrites ()
	Get the last time that the connection was used to commit a write.

	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.

	limitResult ( $sql, $limit, $offset=false)
	Construct a LIMIT query with optional offset.

	listTables ( $prefix=null, $fname=__METHOD__)
	List all tables on the database.

	lock ( $lockName, $method, $timeout=5, $flags=0)
	Acquire a named lock.

	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)

	makeList (array $a, $mode=self::LIST_COMMA)
	Makes an encoded list of strings from an array.

	makeWhereFrom2d ( $data, $baseKey, $subKey)
	Build a "OR" condition with pairs from a two-dimensional array.

	newDeleteQueryBuilder ()
	Get an DeleteQueryBuilder bound to this connection.

	newInsertQueryBuilder ()
	Get an InsertQueryBuilder bound to this connection.

	newReplaceQueryBuilder ()
	Get an ReplaceQueryBuilder bound to this connection.

	newSelectQueryBuilder ()
	Create an empty SelectQueryBuilder which can be used to run queries against this connection.

	newUnionQueryBuilder ()
	Create an empty UnionQueryBuilder which can be used to run queries against this connection.

	newUpdateQueryBuilder ()
	Get an UpdateQueryBuilder bound to this connection.

	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.

	orExpr (array $conds)
	See Expression::__construct()

	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 (&$rtt=null)

	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.

	replace ( $table, $uniqueKeys, $rows, $fname=__METHOD__)
	Insert row(s) into a table, in the provided order, while deleting conflicting rows.

	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()

	select ( $tables, $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 ( $tables, $var, $cond='', $fname=__METHOD__, $options=[], $join_conds=[])
	A SELECT wrapper which returns a single field from a single result row.

	selectFieldValues ( $tables, $var, $cond='', $fname=__METHOD__, $options=[], $join_conds=[])
	A SELECT wrapper which returns a list of single field values from result rows.

	selectRow ( $tables, $vars, $conds, $fname=__METHOD__, $options=[], $join_conds=[])
	Wrapper to IDatabase::select() that only fetches one row (via LIMIT)

	selectRowCount ( $tables, $vars=' *', $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
	Get the number of rows in dataset.

	selectSQLText ( $tables, $vars, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
	Take the same arguments as IDatabase::select() and return the SQL it would use.

	serverIsReadOnly ()

	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.

	setSchemaVars ( $vars)
	Set schema variables to be used when streaming commands from SQL files or stdin.

	setSessionOptions (array $options)
	Override database's default behavior.

	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.

	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=IDatabase::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.

	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')

	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.

	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.

	truncateTable ( $table, $fname=__METHOD__)
	Delete all data in a table and reset any sequences owned by that table.

	trxLevel ()
	Gets the current transaction level.

	trxTimestamp ()
	Get the UNIX timestamp of the time that the transaction was established.

	unionQueries ( $sqls, $all, $options=[])
	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.

	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.

	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\IReadableDatabase
	ping ()
	Ping the server and try to reconnect if it there is no connection.

Public Member Functions inherited from Wikimedia\Rdbms\Platform\ISQLPlatform
	buildSubString ( $input, $startPosition, $length=null)
	Build a SUBSTRING function.

	tableName (string $name, $format='quoted')
	Format a table name ready for use in constructing an SQL query.

Protected Member Functions
	assertRoleAllowsWrites ()
	Error out if the role is not DB_PRIMARY.

	getDomainChangeException ()

	normalizeServerIndex ( $i)

Additional Inherited Members
Public Attributes inherited from Wikimedia\Rdbms\IDatabase
const	ATOMIC_CANCELABLE = 'cancelable'
	Atomic section is cancelable.

const	ATOMIC_NOT_CANCELABLE = ''
	Atomic section is not cancelable.

const	ESTIMATE_DB_APPLY = 'apply'
	Estimate time to apply (scanning, applying)

const	ESTIMATE_TOTAL = 'total'
	Estimate total time (RTT, scanning, waiting on locks, applying)

const	FLUSHING_ALL_PEERS = 'flush'
	Commit/rollback is from the owning connection manager for the IDatabase handle.

const	FLUSHING_INTERNAL = 'flush-internal'
	Commit/rollback is from the IDatabase handle internally.

const	FLUSHING_ONE = ''
	Commit/rollback is from outside the IDatabase handle and connection manager.

const	LB_READ_ONLY_REASON = 'readOnlyReason'
	Field for getLBInfo()/setLBInfo()

const	LB_TRX_ROUND_ID = 'trxRoundId'
	Field for getLBInfo()/setLBInfo()

const	LOCK_TIMESTAMP = 1
	Flag to return the lock acquisition timestamp (null if not acquired)

const	ROLE_STATIC_CLONE = 'static-clone'
	Replica server within a static dataset.

const	ROLE_STREAMING_MASTER = 'streaming-master'
	Primary server than can stream writes to replica servers.

const	ROLE_STREAMING_REPLICA = 'streaming-replica'
	Replica server that receives writes from a primary server.

const	ROLE_UNKNOWN = 'unknown'
	Server with unknown topology role.

const	TRANSACTION_EXPLICIT = ''
	Transaction is requested by regular caller outside of the DB layer.

const	TRANSACTION_INTERNAL = 'implicit'
	Transaction is requested internally via DBO_TRX/startAtomic()

const	TRIGGER_CANCEL = 4
	Callback triggered by atomic section cancel (ROLLBACK TO SAVEPOINT)

const	TRIGGER_COMMIT = 2
	Callback triggered by COMMIT.

const	TRIGGER_IDLE = 1
	Callback triggered immediately due to no active transaction.

const	TRIGGER_ROLLBACK = 3
	Callback triggered by ROLLBACK.

Public Attributes inherited from Wikimedia\Rdbms\IReadableDatabase
const	UNION_ALL = true
	Parameter to unionQueries() for UNION ALL.

const	UNION_DISTINCT = false
	Parameter to unionQueries() for UNION DISTINCT.

Public Attributes inherited from Wikimedia\Rdbms\Platform\ISQLPlatform
const	ALL_ROWS = '*'
	Unconditional update/delete of whole table.

const	CALLER_SUBQUERY = 'subquery'
	Special value for ->caller() / $fname parameter used when providing a caller is not expected, because we're formatting a subquery that won't be executed directly.

const	CALLER_UNKNOWN = 'unknown'
	Special value for ->caller() / $fname parameter used when a caller is not provided.

const	LIST_AND = 1
	Combine list with AND clauses.

const	LIST_COMMA = 0
	Combine list with comma delimiters.

const	LIST_NAMES = 3
	Treat as field name and do not apply value escaping.

const	LIST_OR = 4
	Combine list with OR clauses.

const	LIST_SET = 2
	Convert map into a SET clause.

const	QUERY_CHANGE_LOCKS = 512
	Query is a command for advisory locks.

const	QUERY_CHANGE_NONE = 32
	Query is a read-only Data Query Language query.

const	QUERY_CHANGE_ROWS = 128
	Query is a Data Manipulation Language command (INSERT, DELETE, LOCK, ...)

const	QUERY_CHANGE_SCHEMA = 256
	Query is a Data Definition Language command.

const	QUERY_CHANGE_TRX = 64
	Query is a Transaction Control Language command (BEGIN, USE, SET, ...)

const	QUERY_IGNORE_DBO_TRX = 8
	Ignore the current presence of any DBO_TRX flag.

const	QUERY_NO_RETRY = 16
	Do not try to retry the query if the connection was lost.

const	QUERY_NORMAL = 0
	Idiom for "no special flags".

const	QUERY_PSEUDO_PERMANENT = 2
	Track a TEMPORARY table CREATE as if it was for a permanent table (for testing)

const	QUERY_REPLICA_ROLE = 4
	Enforce that a query does not make effective writes.

const	QUERY_SILENCE_ERRORS = 1
	Ignore query errors and return false when they happen.

Public Attributes inherited from Wikimedia\Rdbms\Database\IDatabaseFlags
const	DBO_COMPRESS = 512
	Enable compression in connection protocol.

const	DBO_DDLMODE = 128
	Schema file mode; was used by Oracle.

const	DBO_DEBUG = 1
	Enable debug logging of all SQL queries.

const	DBO_DEFAULT = 16
	Join load balancer transaction rounds (which control DBO_TRX) in non-CLI mode.

const	DBO_GAUGE = 1024
	Optimize connection for guaging server state (e.g.

const	DBO_IGNORE = 4
	Unused since 1.31.

const	DBO_NOBUFFER = 2
	Unused since 1.34.

const	DBO_PERSISTENT = 32
	Use DB persistent connections if possible.

const	DBO_SSL = 256
	Enable SSL/TLS in connection protocol.

const	DBO_SYSDBA = 64
	DBA session mode; was used by Oracle.

const	DBO_TRX = 8
	Automatically start a transaction before running a query if none is active.

const	REMEMBER_NOTHING = ''
	Do not remember the prior flags.

const	REMEMBER_PRIOR = 'remember'
	Remember the prior flags.

const	RESTORE_INITIAL = 'initial'
	Restore to the initial flag state.

const	RESTORE_PRIOR = 'prior'
	Restore to the prior flag state.

Detailed Description

Helper class used for automatically re-using IDatabase connections and lazily establishing the actual network connection to a database host.

It does this by deferring to ILoadBalancer::getConnectionInternal, which in turn ensures we share and re-use a single connection for a given database wherever possible.

This class previously used an RAII-style pattern where connections would be claimed from a pool, and then added back to the pool for re-use only after the calling code's variable for this object went out of scope (a __destruct got called when the calling function returns or throws). This is no longer needed today as LoadBalancer now permits re-use internally even for overlapping callers, where two pieces of code may both obtain their own DBConnRef object and where both are used alternatingly, and yet still share the same connection.

Example:: function getRowData() {

$conn = $this->lb->getConnection( DB_REPLICA );

$row = $conn->select( ... );

return $row ? (array)$row : false;

}

DB_REPLICA
const DB_REPLICA
Definition defines.php:26

Since: 1.22

Definition at line 37 of file DBConnRef.php.

Constructor & Destructor Documentation

◆ __construct()

Wikimedia\Rdbms\DBConnRef::__construct	(	ILoadBalancer	$lb,
			$params,
			$role,
		&	$modcount = 0 )

Access: internal: May not be used outside Rdbms LoadBalancer

Parameters

ILoadBalancer	$lb	Connection manager for $conn
array	$params	[server index, query groups, domain, flags]
int	$role	The type of connection asked for; one of DB_PRIMARY/DB_REPLICA
null \| int	&$modcount	Reference to a modification counter. This is for LoadBalancer::reconfigure to indicate that a new connection should be acquired.

Definition at line 75 of file DBConnRef.php.

References $params, and Wikimedia\Rdbms\DatabaseDomain\newFromId().

Member Function Documentation

◆ __call()

Wikimedia\Rdbms\DBConnRef::__call	(		$name,
		array	$arguments )

Definition at line 124 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\ensureConnection().

◆ __toString()

Wikimedia\Rdbms\DBConnRef::__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 850 of file DBConnRef.php.

◆ addIdentifierQuotes()

Wikimedia\Rdbms\DBConnRef::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 540 of file DBConnRef.php.

◆ addQuotes()

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

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

Parameters

?scalar | RawSQLValue | Blob $s

Returns: string

Implements Wikimedia\Rdbms\Database\DbQuoter.

Definition at line 521 of file DBConnRef.php.

◆ affectedRows()

Wikimedia\Rdbms\DBConnRef::affectedRows ( )

Get the number of rows affected by the last query method call.

This method should only be called when all the following hold true:

(a) A method call was made to insert(), upsert(), replace(), update(), delete(), insertSelect(), query() with a non-SELECT statement, or queryMulti() with a non-SELECT terminal statement
(b) The method call succeeded
(c) No subsequent method calls were made, with the exception of affectedRows(), lastErrno(), lastError(), and getType()

In all other cases, the return value is unspecified.

UPDATE queries consider rows affected even when all their new column values match the previous values. Such rows can be excluded from the count by changing the WHERE clause to filter them out.

If the last query method call was to query() or queryMulti(), then the results are based on the (last) statement provided to that call and are driver-specific.

Returns: int

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 280 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ andExpr()

Wikimedia\Rdbms\DBConnRef::andExpr ( array $conds )

See Expression::__construct()

Since: 1.43

Parameters

Returns: AndExpressionGroup

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 530 of file DBConnRef.php.

◆ anyChar()

Wikimedia\Rdbms\DBConnRef::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 548 of file DBConnRef.php.

◆ anyString()

Wikimedia\Rdbms\DBConnRef::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 552 of file DBConnRef.php.

◆ assertRoleAllowsWrites()

Wikimedia\Rdbms\DBConnRef::assertRoleAllowsWrites ( )

protected

Error out if the role is not DB_PRIMARY.

Note that the underlying connection may or may not itself be read-only. It could even be to a writable primary (both server-side and to the application). This error is meant for the case when a DB_REPLICA handle was requested but a a write was attempted on that handle regardless.

In configurations where the primary DB has some generic read load or is the only server, DB_PRIMARY/DB_REPLICA will sometimes (or always) use the same connection to the primary DB. This does not effect the role of DBConnRef instances.

Exceptions

DBReadOnlyRoleError

Definition at line 871 of file DBConnRef.php.

◆ begin()

Wikimedia\Rdbms\DBConnRef::begin	(		$fname = __METHOD__,
			$mode = IDatabase::TRANSACTION_EXPLICIT )

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	$fname	Calling function name
string	$mode	A situationally valid IDatabase::TRANSACTION_* constant [optional]

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 668 of file DBConnRef.php.

◆ bitAnd()

Wikimedia\Rdbms\DBConnRef::bitAnd	(		$fieldLeft,
			$fieldRight )

Parameters

string \| int	$fieldLeft
string \| int	$fieldRight

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 436 of file DBConnRef.php.

◆ bitNot()

Wikimedia\Rdbms\DBConnRef::bitNot ( $field )

Parameters

string | int $field

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 432 of file DBConnRef.php.

◆ bitOr()

Wikimedia\Rdbms\DBConnRef::bitOr	(		$fieldLeft,
			$fieldRight )

Parameters

string \| int	$fieldLeft
string \| int	$fieldRight

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 440 of file DBConnRef.php.

◆ buildComparison()

Wikimedia\Rdbms\DBConnRef::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.

When comparing a single value, prefer using the expression builder:

$db->expr( 'key', '<=', $val )

// equivalent to:
$db->buildComparison( '<=', [ 'key' => $val ] )
'key <= ' . $db->addQuotes( $val )

Parameters

string	$op	Comparison operator, one of '>', '>=', '<', '<='
	non-empty-array<string,mixed>	$conds Map of field names to their values to use in the comparison

Returns: string SQL code

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 416 of file DBConnRef.php.

◆ buildConcat()

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

Build a concatenation list to feed into a SQL query.

Parameters

string[] $stringList Raw SQL expression list; caller is responsible for escaping

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 444 of file DBConnRef.php.

◆ buildExcludedValue()

Wikimedia\Rdbms\DBConnRef::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 $column Column name

Returns: string SQL expression returning a scalar

Since: 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 474 of file DBConnRef.php.

◆ buildGreatest()

Wikimedia\Rdbms\DBConnRef::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[]	$fields	Name(s) of column(s) with values to compare
string \| int \| float \| string[] \| int[] \| float[]	$values	Values to compare

Returns: mixed

Since: 1.35 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 454 of file DBConnRef.php.

◆ buildGroupConcatField()

Wikimedia\Rdbms\DBConnRef::buildGroupConcatField	(	$delim,
		$tables,
		$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	$delim	Glue to bind the results together
string \| array	$tables	Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>". {

See also: select} for details.

Parameters

string	$field	Field name
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Conditions
string \| array	$join_conds	Join conditions

Returns: string SQL text

Since: 1.23

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 448 of file DBConnRef.php.

◆ buildIntegerCast()

Wikimedia\Rdbms\DBConnRef::buildIntegerCast ( $field )

Parameters

string $field Field 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 470 of file DBConnRef.php.

◆ buildLeast()

Wikimedia\Rdbms\DBConnRef::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[]	$fields	Name(s) of column(s) with values to compare
string \| int \| float \| string[] \| int[] \| float[]	$values	Values to compare

Returns: mixed

Since: 1.35 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 458 of file DBConnRef.php.

◆ buildLike()

Wikimedia\Rdbms\DBConnRef::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 the 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 544 of file DBConnRef.php.

◆ buildSelectSubquery()

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

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

See also: IDatabase::selectSQLText()

Parameters

string | array $tables Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>". {

See also: select} for details.

Parameters

string \| array	$vars	Field names
string \| array	$conds	Conditions
string	$fname	Caller function name
string \| array	$options	Query options
string \| array	$join_conds	Join conditions

Returns: Subquery

Since: 1.31

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 478 of file DBConnRef.php.

◆ buildStringCast()

Wikimedia\Rdbms\DBConnRef::buildStringCast ( $field )

Parameters

string $field Field 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 466 of file DBConnRef.php.

◆ buildSubstring()

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

Definition at line 462 of file DBConnRef.php.

◆ cancelAtomic()

Wikimedia\Rdbms\DBConnRef::cancelAtomic	(		$fname = __METHOD__,
		?AtomicSectionIdentifier	$sectionId = null )

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	$sectionId	Section ID from startAtomic(); passing this enables cancellation of unclosed nested sections [optional]

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 656 of file DBConnRef.php.

◆ clearFlag()

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

Clear a flag for this connection.

Parameters

int	$flag	One of (IDatabase::DBO_DEBUG, IDatabase::DBO_TRX)
string	$remember	IDatabase::REMEMBER_* constant [default: REMEMBER_NOTHING]

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 230 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ close()

Wikimedia\Rdbms\DBConnRef::close ( $fname = __METHOD__ )

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 $fname Caller name

Returns: bool Success

Exceptions

DBError

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 292 of file DBConnRef.php.

◆ commit()

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

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	$flush	Flush 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

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 672 of file DBConnRef.php.

◆ conditional()

Wikimedia\Rdbms\DBConnRef::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\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>>\|array<int,string\|IExpression>	$cond SQL condition expression (yields a boolean)
string	$caseTrueExpression	SQL expression to return when the condition is true
string	$caseFalseExpression	SQL expression to return when the condition is false

Returns: string SQL fragment

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 601 of file DBConnRef.php.

◆ databasesAreIndependent()

Wikimedia\Rdbms\DBConnRef::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

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 485 of file DBConnRef.php.

◆ dbSchema()

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

Get/set the db schema.

Parameters

string | null $schema The database schema to set, or omitted to leave it unchanged

Returns: string The previous db schema

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 171 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call(), and Wikimedia\Rdbms\DBConnRef\getDomainChangeException().

◆ decodeBlob()

Wikimedia\Rdbms\DBConnRef::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

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 714 of file DBConnRef.php.

◆ decodeExpiry()

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

Decode an expiry time into a DBMS independent format.

Parameters

string	$expiry	DB timestamp field value for expiry
int	$format	TS_* constant, defaults to TS_MW

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 758 of file DBConnRef.php.

◆ delete()

Wikimedia\Rdbms\DBConnRef::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.

Access: internal: callers outside of rdbms library should use DeleteQueryBuilder instead.

Parameters

string	$table	The unqualified name of a table
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Array 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	$fname	Name of the calling function

Returns: bool Return true if no exception was thrown (deprecated since 1.33)

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 578 of file DBConnRef.php.

◆ deleteJoin()

Wikimedia\Rdbms\DBConnRef::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	$delTable	The unqualified name of the table to delete rows from.
string	$joinTable	The unqualified name of the reference table to join on.
string	$delVar	The variable to join on, in the first table.
string	$joinVar	The variable to join on, in the second table.
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Condition array of field names mapped to variables, ANDed together in the WHERE clause
string	$fname	Calling function name (use METHOD) for logs/profiling

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 570 of file DBConnRef.php.

◆ doAtomicSection()

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

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	$fname	Caller name (usually METHOD)
callable	$callback	Callback that issues write queries
string	$cancelable	Pass self::ATOMIC_CANCELABLE to use a savepoint and enable self::cancelAtomic() for this section.

Returns: mixed Result of the callback (since 1.28)

Exceptions

DBError If an error occurs, {

See also: query}

Exceptions

Exception If 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 661 of file DBConnRef.php.

◆ dropTable()

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

Delete a table.

Parameters

string	$table	The unqualified name of a table
string	$fname

Returns: bool Whether the table already existed

Exceptions

DBError If an error occurs

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 814 of file DBConnRef.php.

◆ duplicateTableStructure()

Wikimedia\Rdbms\DBConnRef::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	$oldName	Name of table whose structure should be copied
string	$newName	Name of table to be created
bool	$temporary	Whether the new table should be temporary
string	$fname	Calling function name

Returns: bool True if operation was successful

Exceptions

RuntimeException

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 830 of file DBConnRef.php.

◆ encodeBlob()

Wikimedia\Rdbms\DBConnRef::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

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 710 of file DBConnRef.php.

◆ encodeExpiry()

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

Encode an expiry time into the DBMS dependent format.

Parameters

string $expiry Timestamp for expiry, or the 'infinity' string

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 754 of file DBConnRef.php.

◆ endAtomic()

Wikimedia\Rdbms\DBConnRef::endAtomic ( $fname = __METHOD__ )

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

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 651 of file DBConnRef.php.

◆ ensureConnection()

Wikimedia\Rdbms\DBConnRef::ensureConnection ( )

Connect to the database if we are not already connected.

Definition at line 94 of file DBConnRef.php.

Referenced by Wikimedia\Rdbms\DBConnRef\__call().

◆ estimateRowCount()

Wikimedia\Rdbms\DBConnRef::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.

Access: internal

Parameters

string | string[] $tables Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>". {

See also: select} for details.

Parameters

string	$var	Column for which NULL values are not counted [default "*"]
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Filters on the table
string	$fname	Function name for profiling
array	$options	Options for select
array \| string	$join_conds	Join conditions

Returns: int Row count

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 372 of file DBConnRef.php.

◆ explicitTrxActive()

Wikimedia\Rdbms\DBConnRef::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 150 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ expr()

Wikimedia\Rdbms\DBConnRef::expr	(	string	$field,
		string	$op,
			$value )

See Expression::__construct()

Since: 1.42

Parameters

string	$field
string	$op	One of '>', '<', '!=', '=', '>=', '<=', IExpression::LIKE, IExpression::NOT_LIKE
	?scalar\|RawSQLValue\|Blob\|LikeValue\|non-empty-list<scalar\|Blob>	$value

Returns: Expression

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 525 of file DBConnRef.php.

◆ factorConds()

Wikimedia\Rdbms\DBConnRef::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 $condsArray An 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 428 of file DBConnRef.php.

◆ fieldExists()

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

Determines whether a field exists in a table.

Parameters

string	$table	The unqualified name of a table
string	$field	Field to check on that table
string	$fname	Calling function name

Returns: bool Whether $table has field $field

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 392 of file DBConnRef.php.

◆ fieldInfo()

Wikimedia\Rdbms\DBConnRef::fieldInfo	(		$table,
			$field )

Get information about a field Returns false if the field doesn't exist.

Parameters

string	$table	The unqualified name of a table
string	$field	Field name

Returns: false|Field

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 846 of file DBConnRef.php.

◆ flushSession()

Wikimedia\Rdbms\DBConnRef::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	$fname	Calling function name
string	$flush	Flush 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

DBError If an error occurs, {

See also: query}

Since: 1.38

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 680 of file DBConnRef.php.

◆ flushSnapshot()

Wikimedia\Rdbms\DBConnRef::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	$fname	Calling function name
string	$flush	Flush 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

DBError If an error occurs, {

See also: query}

Since: 1.28; 1.34 Added $flush parameter

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 684 of file DBConnRef.php.

◆ getDBname()

Wikimedia\Rdbms\DBConnRef::getDBname ( )

Get the current database name; null if there isn't one.

Returns: string|null

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 495 of file DBConnRef.php.

◆ getDomainChangeException()

Wikimedia\Rdbms\DBConnRef::getDomainChangeException ( )

protected

Returns: DBUnexpectedError

Definition at line 881 of file DBConnRef.php.

Referenced by Wikimedia\Rdbms\DBConnRef\dbSchema(), Wikimedia\Rdbms\DBConnRef\setLBInfo(), and Wikimedia\Rdbms\DBConnRef\tablePrefix().

◆ getDomainID()

Wikimedia\Rdbms\DBConnRef::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 246 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ getFlag()

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

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

Parameters

int $flag One of the class IDatabase::DBO_* constants

Returns: bool

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 238 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ getInfinity()

Wikimedia\Rdbms\DBConnRef::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 750 of file DBConnRef.php.

◆ getLag()

Wikimedia\Rdbms\DBConnRef::getLag ( )

Get the seconds of replication lag on 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

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 702 of file DBConnRef.php.

◆ getLBInfo()

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

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

Access: internal: should not be called outside of rdbms library.

Parameters

string | null $name The 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 188 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ getPrimaryPos()

Wikimedia\Rdbms\DBConnRef::getPrimaryPos ( )

Get the replication position of this primary DB server.

Returns: DBPrimaryPos|false Position; false if this is not a primary DB

Exceptions

DBError If an error occurs, {

See also: query}

Since: 1.37

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 613 of file DBConnRef.php.

◆ getProperty()

Wikimedia\Rdbms\DBConnRef::getProperty ( $name )

Definition at line 242 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ getReferenceRole()

Wikimedia\Rdbms\DBConnRef::getReferenceRole ( )

Returns: int DB_PRIMARY when this requires the primary DB, otherwise DB_REPLICA

Since: 1.33

Definition at line 134 of file DBConnRef.php.

◆ getScopedLockAndFlush()

Wikimedia\Rdbms\DBConnRef::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	$lockKey	Name of lock to release
string	$fname	Name of the calling method
int	$timeout	Acquisition timeout in seconds

Returns: ScopedCallback|null

Exceptions

DBError If an error occurs, {

See also: query}

Since: 1.27

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 744 of file DBConnRef.php.

◆ getServer()

Wikimedia\Rdbms\DBConnRef::getServer ( )

Get the hostname or IP address of the server.

Returns: string|null

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 504 of file DBConnRef.php.

◆ getServerInfo()

Wikimedia\Rdbms\DBConnRef::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 138 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ getServerName()

Wikimedia\Rdbms\DBConnRef::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 508 of file DBConnRef.php.

◆ getServerVersion()

Wikimedia\Rdbms\DBConnRef::getServerVersion ( )

A string describing the current software version.

Returns: string Version information from the database server.

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 288 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ getSessionLagStatus()

Wikimedia\Rdbms\DBConnRef::getSessionLagStatus ( )

Get a cached estimate of the seconds of replication lag on this database server, using the estimate obtained at the start of the current transaction if one 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

DBError If an error occurs, {

See also: query}

Since: 1.27

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 706 of file DBConnRef.php.

◆ getSoftwareLink()

Wikimedia\Rdbms\DBConnRef::getSoftwareLink ( )

Returns a wikitext style link to the DB's website (e.g.

"[https://www.mysql.com/ MySQL]")

Should at least contain plain text, if for some reason your database has no website.

Returns: string Wikitext of a link to the server software's web site

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 284 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ getTableAliases()

Wikimedia\Rdbms\DBConnRef::getTableAliases ( )

Return current table aliases.

Access: internal: only to be used inside rdbms library

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 770 of file DBConnRef.php.

◆ getType()

Wikimedia\Rdbms\DBConnRef::getType ( )

Get the RDBMS type of the server (e.g.

"mysql", "sqlite")

Returns: string

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 255 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call(), and Wikimedia\Rdbms\DBConnRef\normalizeServerIndex().

◆ implicitOrderby()

Wikimedia\Rdbms\DBConnRef::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 198 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ indexExists()

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

Determines whether an index exists.

Parameters

string	$table	The unqualified name of a table
string	$index
string	$fname

Returns: bool

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 396 of file DBConnRef.php.

◆ indexUnique()

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

Determines if a given index is unique.

Parameters

string	$table	The unqualified name of a table
string	$index
string	$fname	Calling function name

Returns: bool|null Returns null if the index does not exist

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 838 of file DBConnRef.php.

◆ insert()

Wikimedia\Rdbms\DBConnRef::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.

Access: internal: callers outside of rdbms library should use InsertQueryBuilder instead.

Parameters

string	$table	The unqualified name of a table
array \| array[]	$rows	Row(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	$fname	Calling function name (use METHOD) for logs/profiling
string \| array	$options	Combination 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

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 404 of file DBConnRef.php.

◆ insertId()

Wikimedia\Rdbms\DBConnRef::insertId ( )

Get the sequence-based ID assigned by the last query method call.

This method should only be called when all the following hold true:

(a) A method call was made to insert(), upsert(), replace(), or insertSelect()
(b) The method call attempts to insert exactly one row
(c) The method call omits the value of exactly one auto-increment column
(d) The method call succeeded
(e) No subsequent method calls were made, with the exception of affectedRows(), lastErrno(), lastError(), and getType()

In all other cases, the return value is unspecified.

When the query method is either insert() with "IGNORE", upsert(), or insertSelect(), callers should first check affectedRows() before calling this method, making sure that the query method actually created a row. Otherwise, an ID from a previous insert might be incorrectly assumed to belong to last insert.

Returns: int

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 268 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ insertSelect()

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

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	$destTable	Unqualified name of destination table
string \| array	$srcTable	Unqualified name of source table(s) (use an array for a join)
array	$varMap	Must 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()
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Condition array. See $conds in IDatabase::select() for the details of the format of condition arrays. May be "*" to copy the whole table.
string	$fname	The function name of the caller, from METHOD
array	$insertOptions	Options 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	$selectOptions	Options for the SELECT part of the query, see IDatabase::select() for details.
array	$selectJoinConds	Join 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

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 584 of file DBConnRef.php.

◆ isOpen()

Wikimedia\Rdbms\DBConnRef::isOpen ( )

Returns: bool Whether a connection to the database open

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 222 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ isReadOnly()

Wikimedia\Rdbms\DBConnRef::isReadOnly ( )

Check if this DB server is marked as read-only according to load balancer info.

Note: LoadBalancer checks serverIsReadOnly() when setting the load balancer info array

Returns: bool

Since: 1.27

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 762 of file DBConnRef.php.

◆ lastDoneWrites()

Wikimedia\Rdbms\DBConnRef::lastDoneWrites ( )

Get the last time that the connection was used to commit a write.

Access: internal: Should only be called from the rdbms library.

Returns: float|null UNIX timestamp; null if no writes were committed

Since: 1.24

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 202 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ lastErrno()

Wikimedia\Rdbms\DBConnRef::lastErrno ( )

Get the RDBMS-specific error code from the last attempted query statement.

Returns: int|string Error code (integer or hexadecimal depending on RDBMS type)

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 272 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ lastError()

Wikimedia\Rdbms\DBConnRef::lastError ( )

Get the RDBMS-specific error description from the last attempted query statement.

Returns: string

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 276 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ limitResult()

Wikimedia\Rdbms\DBConnRef::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	$sql	SQL query we will append the limit too
int	$limit	The SQL limit
int \| false	$offset	The 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 361 of file DBConnRef.php.

◆ listTables()

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

List all tables on the database.

Since MW 1.42, this will no longer include MySQL views.

Parameters

string \| null	$prefix	Only show tables with this prefix, e.g. mw_
string	$fname	Calling function name

Exceptions

DBError

Returns: array

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 842 of file DBConnRef.php.

◆ lock()

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

Acquire a named lock.

Named locks are not related to transactions

Parameters

string	$lockName	Name of lock to acquire
string	$method	Name of the calling method
int	$timeout	Acquisition timeout in seconds (0 means non-blocking)
int	$flags	Bit field of IDatabase::LOCK_* constants

Returns: bool|float|null Success (bool); acquisition time (float/null) if LOCK_TIMESTAMP

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 732 of file DBConnRef.php.

◆ lockForUpdate()

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

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

Parameters

string \| string[]	$table	The unqualified name of table(s) (use an array for a join)
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Condition in the format of IDatabase::select() conditions
string	$fname	Function name for profiling
array	$options	Options for select ("FOR UPDATE" is added automatically)
array	$join_conds	Join conditions

Returns: int Number of matching rows found (and locked)

Exceptions

DBError If an error occurs, {

See also: query}

Since: 1.32

Deprecated: since 1.43; Use SelectQueryBuilder::acquireRowLocks

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 384 of file DBConnRef.php.

◆ lockIsFree()

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

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

Parameters

string	$lockName	Name of lock to poll
string	$method	Name of method calling us

Returns: bool

Exceptions

DBError If an error occurs, {

See also: query}

Since: 1.20

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 726 of file DBConnRef.php.

◆ makeList()

Wikimedia\Rdbms\DBConnRef::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	$a	Containing the data
int	$mode	IDatabase 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

DBError If an error occurs, {

See also: IDatabase::query}

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 420 of file DBConnRef.php.

◆ makeWhereFrom2d()

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

Build a "OR" condition with pairs from a two-dimensional array.

The associative array should have integer keys relating to the $baseKey field. The nested array should have string keys for the $subKey field. The inner values are ignored, and are typically boolean true.

Example usage:

$data = [
    2 => [
        'Foo' => true,
        'Bar' => true,
    ],
    3 => [
        'Quux' => true,
    ],
];
// (page_namespace = 2 AND page_title IN ('Foo','Bar'))
// OR (page_namespace = 3 AND page_title = 'Quux')

Todo: This is effectively specific to MediaWiki's LinkBatch. Consider deprecating or generalising slightly.

Parameters

array	$data	Nested array, must be non-empty
string	$baseKey	Field name to match the base-level keys to (eg 'pl_namespace')
string	$subKey	Field name to match the sub-level keys to (eg 'pl_title')

Returns: string SQL fragment

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 424 of file DBConnRef.php.

◆ newDeleteQueryBuilder()

Wikimedia\Rdbms\DBConnRef::newDeleteQueryBuilder ( )

Get an DeleteQueryBuilder bound to this connection.

This is overridden by DBConnRef.

Note: A new query builder must be created per query. Query builders should not be reused since this uses a fluent interface and the state of the builder changes during the query which may cause unexpected results.

Returns: DeleteQueryBuilder

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 320 of file DBConnRef.php.

◆ newInsertQueryBuilder()

Wikimedia\Rdbms\DBConnRef::newInsertQueryBuilder ( )

Get an InsertQueryBuilder bound to this connection.

This is overridden by DBConnRef.

Note: A new query builder must be created per query. Query builders should not be reused since this uses a fluent interface and the state of the builder changes during the query which may cause unexpected results.

Returns: InsertQueryBuilder

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 325 of file DBConnRef.php.

◆ newReplaceQueryBuilder()

Wikimedia\Rdbms\DBConnRef::newReplaceQueryBuilder ( )

Get an ReplaceQueryBuilder bound to this connection.

This is overridden by DBConnRef.

Note: A new query builder must be created per query. Query builders should not be reused since this uses a fluent interface and the state of the builder changes during the query which may cause unexpected results.

Returns: ReplaceQueryBuilder

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 330 of file DBConnRef.php.

◆ newSelectQueryBuilder()

Wikimedia\Rdbms\DBConnRef::newSelectQueryBuilder ( )

Create an empty SelectQueryBuilder which can be used to run queries against this connection.

Note: A new query builder must be created per query. Query builders should not be reused since this uses a fluent interface and the state of the builder changes during the query which may cause unexpected results.

Returns: SelectQueryBuilder

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 305 of file DBConnRef.php.

◆ newUnionQueryBuilder()

Wikimedia\Rdbms\DBConnRef::newUnionQueryBuilder ( )

Create an empty UnionQueryBuilder which can be used to run queries against this connection.

Note: A new query builder must be created per query. Query builders should not be reused since this uses a fluent interface and the state of the builder changes during the query which may cause unexpected results.

Since: 1.41

Returns: UnionQueryBuilder

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 310 of file DBConnRef.php.

◆ newUpdateQueryBuilder()

Wikimedia\Rdbms\DBConnRef::newUpdateQueryBuilder ( )

Get an UpdateQueryBuilder bound to this connection.

This is overridden by DBConnRef.

Note: A new query builder must be created per query. Query builders should not be reused since this uses a fluent interface and the state of the builder changes during the query which may cause unexpected results.

Returns: UpdateQueryBuilder

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 315 of file DBConnRef.php.

◆ normalizeServerIndex()

Wikimedia\Rdbms\DBConnRef::normalizeServerIndex ( $i )

protected

Parameters

int $i Specific or virtual (DB_PRIMARY/DB_REPLICA) server index

Returns: int|mixed

Definition at line 894 of file DBConnRef.php.

Referenced by Wikimedia\Rdbms\DBConnRef\getType().

◆ onAtomicSectionCancel()

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

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	$fname	Caller name

Since: 1.34

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 636 of file DBConnRef.php.

◆ onTransactionCommitOrIdle()

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

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	$fname	Caller name

Exceptions

DBError If an error occurs, {

See also: query}

Exceptions

Exception If the callback runs immediately and an error occurs in it

Since: 1.32

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 626 of file DBConnRef.php.

◆ onTransactionPreCommitOrIdle()

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

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	$fname	Caller name

Exceptions

DBError If an error occurs, {

See also: query}

Exceptions

Exception If the callback runs immediately and an error occurs in it

Since: 1.22

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 631 of file DBConnRef.php.

◆ onTransactionResolution()

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

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	$fname	Caller name

Exceptions

DBError If an error occurs, {

See also: query}

Exceptions

Exception If the callback runs immediately and an error occurs in it

Since: 1.28

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 621 of file DBConnRef.php.

◆ orExpr()

Wikimedia\Rdbms\DBConnRef::orExpr ( array $conds )

See Expression::__construct()

Since: 1.43

Parameters

Returns: OrExpressionGroup

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 535 of file DBConnRef.php.

◆ pendingWriteCallers()

Wikimedia\Rdbms\DBConnRef::pendingWriteCallers ( )

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

Returns: array

Since: 1.27

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 218 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ pendingWriteQueryDuration()

Wikimedia\Rdbms\DBConnRef::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 $type IDatabase::ESTIMATE_* constant [default: ESTIMATE_ALL]

Returns: float|false Returns false if not transaction is active

Since: 1.26

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 214 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ ping()

Wikimedia\Rdbms\DBConnRef::ping ( & $rtt = null )

Definition at line 696 of file DBConnRef.php.

◆ primaryPosWait()

Wikimedia\Rdbms\DBConnRef::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	$timeout	The 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

DBError If an error occurs, {

See also: query}

Since: 1.37

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 609 of file DBConnRef.php.

◆ query()

Wikimedia\Rdbms\DBConnRef::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 \| Query	$sql	Single-statement SQL query
string	$fname	Caller name; used for profiling/SHOW PROCESSLIST comments
int	$flags	Bit field of ISQLPlatform::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

DBQueryError	If the query is issued, fails, and QUERY_SILENCE_ERRORS is not set
DBExpectedError	If the query is not, and cannot, be issued yet (non-DBQueryError)
DBError	If the query is inherently not allowed (non-DBExpectedError)

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 297 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call(), Wikimedia\Rdbms\ILoadBalancer\DB_PRIMARY, and Wikimedia\Rdbms\Platform\ISQLPlatform\QUERY_REPLICA_ROLE.

◆ replace()

Wikimedia\Rdbms\DBConnRef::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.

Access: internal: callers outside of rdbms library should use ReplaceQueryBuilder instead.

Parameters

string	$table	The unqualified name of a table
string \| string[] \| string[][]	$uniqueKeys	Column 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[]	$rows	Row(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	$fname	Calling function name (use METHOD) for logs/profiling

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 556 of file DBConnRef.php.

◆ restoreFlags()

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

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

Parameters

string $state IDatabase::RESTORE_* constant. [default: RESTORE_PRIOR]

Since: 1.28

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 234 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ rollback()

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

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	$fname	Calling function name
string	$flush	Flush 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

DBError If an error occurs, {

See also: query}

Since: 1.23 Added $flush parameter

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 676 of file DBConnRef.php.

◆ select()

Wikimedia\Rdbms\DBConnRef::select	(	$tables,
		$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 $tables Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>".

Each table reference assigns a table name to a specified collection of rows for the context of the query (e.g. field expressions, WHERE clause, GROUP BY clause, HAVING clause, ect...). Use of multiple table references implies a JOIN.

If a string is given, it must hold the name of the table having the specified collection of rows. If an array is given, each entry must be one of the following:

A string holding the name of the existing table which has the collection of rows. If keyed by a string, the key will be the assigned table name.
A Subquery instance which specifies the collection of rows derived from a subquery. If keyed by a string, the key will be the assigned table name. Otherwise, the SQL text of the subquery will be the assigned table name.
An array specifying the collection of rows derived from a parenthesized JOIN. It must be keyed by a string, which will be used as the assigned table name.

String keys allow table aliases to 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 $vars Field 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

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	$fname	Caller function name
string \| array	$options	Query 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 a 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_conds Join 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' ] ]

Access: internal

Returns: IResultWrapper Resulting rows

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 347 of file DBConnRef.php.

◆ selectDomain()

Wikimedia\Rdbms\DBConnRef::selectDomain ( $domain )

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

DBConnectionError	If databasesAreIndependent() is true and connection change fails
DBError	On query error, if domain changes are disallowed, or the domain is invalid

Since: 1.32

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 489 of file DBConnRef.php.

◆ selectField()

Wikimedia\Rdbms\DBConnRef::selectField	(	$tables,
		$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.

Access: internal: callers outside of rdbms library should use SelectQueryBuilder instead.

Parameters

string | array $tables Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>". {

See also: select} for details.

Parameters

string | array $var The 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|IExpression|array<string,?scalar|non-empty-array<int,?scalar>|RawSQLValue>|array<int,string|IExpression> $cond The condition array. {

See also: select} for details.

Parameters

string	$fname	The function name of the caller.
string \| array	$options	The query options. {

See also: select} for details.

Parameters

string | array $join_conds The query join conditions. {

See also: select} for details.

Returns: mixed|false The value from the field, or false if nothing was found

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 335 of file DBConnRef.php.

◆ selectFieldValues()

Wikimedia\Rdbms\DBConnRef::selectFieldValues	(	$tables,
		$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.

Access: internal: callers outside of rdbms library should use SelectQueryBuilder instead.

Parameters

string | array $tables Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>". {

See also: select} for details.

Parameters

string	$var	The field name to select. This must be a valid SQL fragment: do not use unvalidated user input.
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$cond The condition array. {

See also: select} for details.

Parameters

string	$fname	The function name of the caller.
string \| array	$options	The query options. {

See also: select} for details.

Parameters

string | array $join_conds The 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

DBError If an error occurs, {

See also: query}

Since: 1.25

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 341 of file DBConnRef.php.

◆ selectRow()

Wikimedia\Rdbms\DBConnRef::selectRow	(	$tables,
		$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.

Access: internal

Parameters

string | array $tables Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>". {

See also: select} for details.

Parameters

string \| array	$vars	Field names
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Conditions
string	$fname	Caller function name
string \| array	$options	Query options
array \| string	$join_conds	Join conditions

Returns: stdClass|false

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 365 of file DBConnRef.php.

◆ selectRowCount()

Wikimedia\Rdbms\DBConnRef::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

Access: internal

Parameters

string | string[] $tables Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>". {

See also: select} for details.

Parameters

string	$var	Column for which NULL values are not counted [default "*"]
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Filters on the table
string	$fname	Function name for profiling
array	$options	Options for select
array	$join_conds	Join conditions (since 1.27)

Returns: int Row count

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 378 of file DBConnRef.php.

◆ selectSQLText()

Wikimedia\Rdbms\DBConnRef::selectSQLText	(	$tables,
		$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	$tables	Table reference(s), using the unqualified name of tables or of the form "information_schema.<identifier>".
string \| array	$vars	Field names
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Conditions
string	$fname	Caller function name
string \| array	$options	Query options
string \| array	$join_conds	Join conditions

Returns: string SQL query string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 354 of file DBConnRef.php.

◆ serverIsReadOnly()

Wikimedia\Rdbms\DBConnRef::serverIsReadOnly ( )

Returns: bool Whether this DB server is running in server-side read-only mode

Exceptions

DBError If an error occurs, {

See also: query}

Since: 1.28

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 617 of file DBConnRef.php.

◆ setFlag()

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

Set a flag for this connection.

Parameters

int	$flag	One of (IDatabase::DBO_DEBUG, IDatabase::DBO_TRX)
string	$remember	IDatabase::REMEMBER_* constant [default: REMEMBER_NOTHING]

Implements Wikimedia\Rdbms\Database\IDatabaseFlags.

Definition at line 226 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ setIndexAliases()

Wikimedia\Rdbms\DBConnRef::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 774 of file DBConnRef.php.

◆ setLBInfo()

Wikimedia\Rdbms\DBConnRef::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

Access: internal: should not be called outside of rdbms library.

Parameters

array \| string	$nameOrArray	The new array or the name of a key to set
array \| mixed \| null	$value	If $nameOrArray is a string, the new key value (null to unset)

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 192 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\getDomainChangeException().

◆ setSchemaVars()

Wikimedia\Rdbms\DBConnRef::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 $vars Map of (variable => value) or null to use the defaults

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 722 of file DBConnRef.php.

◆ setSessionOptions()

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

Override database's default behavior.

Not all options are supported on all database backends; unsupported options are silently ignored.

$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. Only supported on MySQL and MariaDB.
'groupConcatMaxLen': Maximum length of a GROUP_CONCAT() result. Only supported on MySQL and MariaDB.

Parameters

array $options

Returns: void

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 718 of file DBConnRef.php.

◆ setTableAliases()

Wikimedia\Rdbms\DBConnRef::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[] $aliases Map of (unqualified name of table => (dbname, schema, prefix) map)

Since: 1.28 in IDatabase, moved to ISQLPlatform in 1.39

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 766 of file DBConnRef.php.

◆ setTransactionListener()

Wikimedia\Rdbms\DBConnRef::setTransactionListener	(		$name,
		?callable	$callback = null )

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	$name	Callback name
callable \| null	$callback	Use null to unset a listener

Since: 1.28

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 640 of file DBConnRef.php.

◆ sourceFile()

Wikimedia\Rdbms\DBConnRef::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	$filename	File name to open
callable \| null	$lineCallback	Optional function called before reading each line
callable \| null	$resultCallback	Optional function called for each MySQL result
string \| false	$fname	Calling function name or false if name should be generated dynamically using $filename
callable \| null	$inputCallback	Optional function called for each complete line sent

Returns: bool|string

Exceptions

Exception

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 790 of file DBConnRef.php.

◆ sourceStream()

Wikimedia\Rdbms\DBConnRef::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	$fp	File handle
callable \| null	$lineCallback	Optional function called before reading each query
callable \| null	$resultCallback	Optional function called for each MySQL result
string	$fname	Calling function name
callable \| null	$inputCallback	Optional function called for each complete query sent

Returns: bool|string

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 802 of file DBConnRef.php.

◆ startAtomic()

Wikimedia\Rdbms\DBConnRef::startAtomic	(		$fname = __METHOD__,
			$cancelable = IDatabase::ATOMIC_NOT_CANCELABLE )

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	$cancelable	Pass self::ATOMIC_CANCELABLE to use a savepoint and enable self::cancelAtomic() for this section.

Returns: AtomicSectionIdentifier section ID token

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 644 of file DBConnRef.php.

◆ streamStatementEnd()

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

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

Parameters

string	&$sql	SQL assembled so far
string	&$newLine	New line about to be added to $sql

Returns: bool Whether $newLine contains end of the statement

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 826 of file DBConnRef.php.

◆ strreplace()

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

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

REPLACE() in mysql)

Parameters

string	$orig	Column to modify
string	$old	Column to seek
string	$new	Column to replace with

Returns: string

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 605 of file DBConnRef.php.

◆ tableExists()

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

Query whether a given table exists.

Parameters

string	$table	The unqualified name of a table
string	$fname

Returns: bool

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 400 of file DBConnRef.php.

◆ tableName()

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

Definition at line 778 of file DBConnRef.php.

◆ tableNames()

Wikimedia\Rdbms\DBConnRef::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 782 of file DBConnRef.php.

◆ tableNamesN()

Wikimedia\Rdbms\DBConnRef::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

Deprecated: Since 1.43; if you must format table names, write several calls to tableName.

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 786 of file DBConnRef.php.

◆ tablePrefix()

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

Get/set the table prefix.

Parameters

string | null $prefix The table prefix to set, or omitted to leave it unchanged

Returns: string The previous table prefix

Implements Wikimedia\Rdbms\IReadableDatabase.

Definition at line 154 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call(), and Wikimedia\Rdbms\DBConnRef\getDomainChangeException().

◆ timestamp()

Wikimedia\Rdbms\DBConnRef::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 688 of file DBConnRef.php.

◆ timestampOrNull()

Wikimedia\Rdbms\DBConnRef::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 692 of file DBConnRef.php.

◆ truncateTable()

Wikimedia\Rdbms\DBConnRef::truncateTable	(		$table,
			$fname = __METHOD__ )

Delete all data in a table and reset any sequences owned by that table.

Parameters

string	$table	The unqualified name of a table
string	$fname

Exceptions

DBError If an error occurs

Since: 1.42

Implements Wikimedia\Rdbms\IMaintainableDatabase.

Definition at line 820 of file DBConnRef.php.

◆ trxLevel()

Wikimedia\Rdbms\DBConnRef::trxLevel ( )

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 142 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ trxTimestamp()

Wikimedia\Rdbms\DBConnRef::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 146 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ unionQueries()

Wikimedia\Rdbms\DBConnRef::unionQueries	(	$sqls,
		$all,
		$options = [] )

Construct a UNION query.

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

Access: internal: callers outside of rdbms library should use UnionQueryBuilder instead.

Parameters

array	$sqls	SQL statements to combine
bool	$all	Either `IDatabase::UNION_ALL` or `IDatabase::UNION_DISTINCT`
array	$options	Query options

Returns: string SQL fragment

Implements Wikimedia\Rdbms\Platform\ISQLPlatform.

Definition at line 597 of file DBConnRef.php.

◆ unionSupportsOrderAndLimit()

Wikimedia\Rdbms\DBConnRef::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 593 of file DBConnRef.php.

◆ unlock()

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

Release a lock.

Named locks are not related to transactions

Parameters

string	$lockName	Name of lock to release
string	$method	Name of the calling method

Returns: bool Success

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 738 of file DBConnRef.php.

◆ update()

Wikimedia\Rdbms\DBConnRef::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.

Access: internal: callers outside of rdbms library should use UpdateQueryBuilder instead.

Parameters

string	$table	The unqualified name of a table
	array<string,?scalar\|RawSQLValue>\|array<int,string>	$set Combination 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.
	string\|IExpression\|array<string,?scalar\|non-empty-array<int,?scalar>\|RawSQLValue>\|array<int,string\|IExpression>	$conds Condition 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	$fname	Calling function name (use METHOD) for logs/profiling
string \| array	$options	Combination 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() includes all matching rows, that includes also rows not updated due to key conflict.

Returns: bool Return true if no exception was thrown (deprecated since 1.33)

Exceptions

DBError If an error occurs, {

See also: query}

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 410 of file DBConnRef.php.

◆ upsert()

Wikimedia\Rdbms\DBConnRef::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.

Access: internal: callers outside of rdbms library should use InsertQueryBuilder instead.

Parameters

string	$table	The unqualified name of a table
array \| array[]	$rows	Row(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[][]	$uniqueKeys	Column 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<string,?scalar\|RawSQLValue>\|array<int,string>	$set Combination 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	$fname	Calling function name (use METHOD) for logs/profiling

Exceptions

DBError If an error occurs, {

See also: query}

Since: 1.22

Implements Wikimedia\Rdbms\IDatabase.

Definition at line 562 of file DBConnRef.php.

◆ writesOrCallbacksPending()

Wikimedia\Rdbms\DBConnRef::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\IDatabaseForOwner.

Definition at line 210 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

◆ writesPending()

Wikimedia\Rdbms\DBConnRef::writesPending ( )

Returns: bool Whether there is a transaction open with possible write queries

Since: 1.27

Implements Wikimedia\Rdbms\IDatabaseForOwner.

Definition at line 206 of file DBConnRef.php.

References Wikimedia\Rdbms\DBConnRef\__call().

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

includes/libs/rdbms/database/DBConnRef.php

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ __construct()

Member Function Documentation

◆ __call()

◆ __toString()

◆ addIdentifierQuotes()

◆ addQuotes()

◆ affectedRows()

◆ andExpr()

◆ anyChar()

◆ anyString()

◆ assertRoleAllowsWrites()

◆ begin()

◆ bitAnd()

◆ bitNot()

◆ bitOr()

◆ buildComparison()

◆ buildConcat()

◆ buildExcludedValue()

◆ buildGreatest()

◆ buildGroupConcatField()

◆ buildIntegerCast()

◆ buildLeast()

◆ buildLike()

◆ buildSelectSubquery()

◆ buildStringCast()

◆ buildSubstring()

◆ cancelAtomic()

◆ clearFlag()

◆ close()

◆ commit()

◆ conditional()

◆ databasesAreIndependent()

◆ dbSchema()

◆ decodeBlob()

◆ decodeExpiry()

◆ delete()

◆ deleteJoin()

◆ doAtomicSection()

◆ dropTable()

◆ duplicateTableStructure()

◆ encodeBlob()

◆ encodeExpiry()

◆ endAtomic()

◆ ensureConnection()

◆ estimateRowCount()

◆ explicitTrxActive()

◆ expr()

◆ factorConds()

◆ fieldExists()

◆ fieldInfo()

◆ flushSession()

◆ flushSnapshot()

◆ getDBname()

◆ getDomainChangeException()

◆ getDomainID()

◆ getFlag()

◆ getInfinity()

◆ getLag()

◆ getLBInfo()

◆ getPrimaryPos()

◆ getProperty()

◆ getReferenceRole()

◆ getScopedLockAndFlush()

◆ getServer()

◆ getServerInfo()

◆ getServerName()

◆ getServerVersion()

◆ getSessionLagStatus()

◆ getSoftwareLink()

◆ getTableAliases()

◆ getType()

◆ implicitOrderby()

◆ indexExists()

◆ indexUnique()

◆ insert()