MediaWiki REL1_35
runBatchedQuery.php
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1<?php
26require_once __DIR__ . '/Maintenance.php';
27
30
37 public function __construct() {
38 parent::__construct();
39 $this->addDescription(
40 "Run an update query on all rows of a table. " .
41 "Waits for replicas at appropriate intervals." );
42 $this->addOption( 'table', 'The table name', true, true );
43 $this->addOption( 'set', 'The SET clause', true, true );
44 $this->addOption( 'where', 'The WHERE clause', false, true );
45 $this->addOption( 'key', 'A column name, the values of which are unique', true, true );
46 $this->addOption( 'batch-size', 'The batch size (default 1000)', false, true );
47 $this->addOption( 'db', 'The database name, or omit to use the current wiki.', false, true );
48 }
49
50 public function execute() {
51 $table = $this->getOption( 'table' );
52 $key = $this->getOption( 'key' );
53 $set = $this->getOption( 'set' );
54 $where = $this->getOption( 'where', null );
55 $where = $where === null ? [] : [ $where ];
56 $batchSize = $this->getOption( 'batch-size', 1000 );
57
58 $dbName = $this->getOption( 'db', null );
59 if ( $dbName === null ) {
60 $dbw = $this->getDB( DB_MASTER );
61 } else {
62 $lbf = MediaWiki\MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
63 $lb = $lbf->getMainLB( $dbName );
64 $dbw = $lb->getConnection( DB_MASTER, [], $dbName );
65 }
66
67 $selectConds = $where;
68 $prevEnd = false;
69 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
70
71 $n = 1;
72 do {
73 $this->output( "Batch $n: " );
74 $n++;
75
76 // Note that the update conditions do not rely on atomicity of the
77 // SELECT query in order to guarantee that all rows are updated. The
78 // results of the SELECT are merely a partitioning hint. Simultaneous
79 // updates merely result in the wrong number of rows being updated
80 // in a batch.
81
82 $res = $dbw->select( $table, $key, $selectConds, __METHOD__,
83 [ 'ORDER BY' => $key, 'LIMIT' => $batchSize ] );
84 if ( $res->numRows() ) {
85 $res->seek( $res->numRows() - 1 );
86 $row = $res->fetchObject();
87 $end = $dbw->addQuotes( $row->$key );
88 $selectConds = array_merge( $where, [ "$key > $end" ] );
89 $updateConds = array_merge( $where, [ "$key <= $end" ] );
90 } else {
91 $updateConds = $where;
92 $end = false;
93 }
94 if ( $prevEnd !== false ) {
95 $updateConds = array_merge( [ "$key > $prevEnd" ], $updateConds );
96 }
97
98 $query = "UPDATE " . $dbw->tableName( $table ) .
99 " SET " . $set .
100 " WHERE " . $dbw->makeList( $updateConds, IDatabase::LIST_AND );
101
102 $dbw->query( $query, __METHOD__ );
103
104 $prevEnd = $end;
105
106 $affected = $dbw->affectedRows();
107 $this->output( "$affected rows affected\n" );
108 $lbFactory->waitForReplication();
109 } while ( $res->numRows() );
110 }
111
112 public function getDbType() {
114 }
115}
116
117$maintClass = RunBatchedQuery::class;
118require_once RUN_MAINTENANCE_IF_MAIN;
getDB()
const RUN_MAINTENANCE_IF_MAIN
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
output( $out, $channel=null)
Throw some output to the user.
addDescription( $text)
Set the description text.
addOption( $name, $description, $required=false, $withArg=false, $shortName=false, $multiOccurrence=false)
Add a parameter to the script.
getOption( $name, $default=null)
Get an option, or return the default.
MediaWikiServices is the service locator for the application scope of MediaWiki.
Maintenance script to run a database query in batches and wait for replica DBs.
__construct()
Default constructor.
execute()
Do the actual work.
getDbType()
Does the script need different DB access? By default, we give Maintenance scripts normal rights to th...
Basic database interface for live and lazy-loaded relation database handles.
Definition IDatabase.php:38
const DB_MASTER
Definition defines.php:29