MediaWiki  master
runBatchedQuery.php
Go to the documentation of this file.
1 <?php
26 require_once __DIR__ . '/Maintenance.php';
27 
29 
36  public function __construct() {
37  parent::__construct();
38  $this->addDescription(
39  "Run an update query on all rows of a table. " .
40  "Waits for replicas at appropriate intervals." );
41  $this->addOption( 'table', 'The table name', true, true );
42  $this->addOption( 'set', 'The SET clause', true, true );
43  $this->addOption( 'where', 'The WHERE clause', false, true );
44  $this->addOption( 'key', 'A column name, the values of which are unique', true, true );
45  $this->addOption( 'batch-size', 'The batch size (default 1000)', false, true );
46  $this->addOption( 'db', 'The database name, or omit to use the current wiki.', false, true );
47  }
48 
49  public function execute() {
50  $table = $this->getOption( 'table' );
51  $key = $this->getOption( 'key' );
52  $set = $this->getOption( 'set' );
53  $where = $this->getOption( 'where', null );
54  $where = $where === null ? [] : [ $where ];
55  $batchSize = $this->getOption( 'batch-size', 1000 );
56 
57  $dbName = $this->getOption( 'db', null );
58  if ( $dbName === null ) {
59  $dbw = $this->getDB( DB_MASTER );
60  } else {
61  $lbf = MediaWiki\MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
62  $lb = $lbf->getMainLB( $dbName );
63  $dbw = $lb->getConnection( DB_MASTER, [], $dbName );
64  }
65 
66  $selectConds = $where;
67  $prevEnd = false;
68 
69  $n = 1;
70  do {
71  $this->output( "Batch $n: " );
72  $n++;
73 
74  // Note that the update conditions do not rely on atomicity of the
75  // SELECT query in order to guarantee that all rows are updated. The
76  // results of the SELECT are merely a partitioning hint. Simultaneous
77  // updates merely result in the wrong number of rows being updated
78  // in a batch.
79 
80  $res = $dbw->select( $table, $key, $selectConds, __METHOD__,
81  [ 'ORDER BY' => $key, 'LIMIT' => $batchSize ] );
82  if ( $res->numRows() ) {
83  $res->seek( $res->numRows() - 1 );
84  $row = $res->fetchObject();
85  $end = $dbw->addQuotes( $row->$key );
86  $selectConds = array_merge( $where, [ "$key > $end" ] );
87  $updateConds = array_merge( $where, [ "$key <= $end" ] );
88  } else {
89  $updateConds = $where;
90  }
91  if ( $prevEnd !== false ) {
92  $updateConds = array_merge( [ "$key > $prevEnd" ], $updateConds );
93  }
94 
95  $query = "UPDATE " . $dbw->tableName( $table ) .
96  " SET " . $set .
97  " WHERE " . $dbw->makeList( $updateConds, IDatabase::LIST_AND );
98 
99  $dbw->query( $query, __METHOD__ );
100 
101  $prevEnd = $end;
102 
103  $affected = $dbw->affectedRows();
104  $this->output( "$affected rows affected\n" );
105  wfWaitForSlaves();
106  } while ( $res->numRows() );
107  }
108 
109  public function getDbType() {
110  return Maintenance::DB_ADMIN;
111  }
112 }
113 
115 require_once RUN_MAINTENANCE_IF_MAIN;
null for the local wiki Added should default to null in handler for backwards compatibility add a value to it if you want to add a cookie that have to vary cache options can modify $query
Definition: hooks.txt:1585
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
getOption( $name, $default=null)
Get an option, or return the default.
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
Definition: maintenance.txt:39
Maintenance script to run a database query in batches and wait for replica DBs.
require_once RUN_MAINTENANCE_IF_MAIN
Definition: maintenance.txt:50
static getInstance()
Returns the global default instance of the top level service locator.
const DB_MASTER
Definition: defines.php:26
const LIST_AND
Definition: Defines.php:39
$res
Definition: database.txt:21
wfWaitForSlaves( $ifWritesSince=null, $wiki=false, $cluster=false, $timeout=null)
Waits for the replica DBs to catch up to the master position.
addDescription( $text)
Set the description text.
const DB_ADMIN
Definition: Maintenance.php:87
this hook is for auditing only or null if authentication failed before getting that far or null if we can t even determine that When $user is not null
Definition: hooks.txt:780
getDB( $db, $groups=[], $wiki=false)
Returns a database to be used by current maintenance script.
output( $out, $channel=null)
Throw some output to the user.
$maintClass
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition: injection.txt:35
you have access to all of the normal MediaWiki so you can get a DB use the etc For full docs on the Maintenance class
Definition: maintenance.txt:52
addOption( $name, $description, $required=false, $withArg=false, $shortName=false, $multiOccurrence=false)
Add a parameter to the script.