MediaWiki REL1_30
runBatchedQuery.php
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1<?php
26require_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" );
106 } while ( $res->numRows() );
107 }
108
109 public function getDbType() {
111 }
112}
113
114$maintClass = "BatchedQueryRunner";
115require_once RUN_MAINTENANCE_IF_MAIN;
wfWaitForSlaves( $ifWritesSince=null, $wiki=false, $cluster=false, $timeout=null)
Waits for the replica DBs to catch up to the master position.
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...
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
getDB( $db, $groups=[], $wiki=false)
Returns a database to be used by current maintenance script.
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.
$res
Definition database.txt:21
design txt This is a brief overview of the new design More thorough and up to date information is available on the documentation wiki at etc Handles the details of getting and saving to the user table of the and dealing with sessions and cookies OutputPage Encapsulates the entire HTML page that will be sent in response to any server request It is used by calling its functions to add in any and then calling output() to send it all. It could be easily changed to send incrementally if that becomes useful
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:1610
Basic database interface for live and lazy-loaded relation database handles.
Definition IDatabase.php:40
require_once RUN_MAINTENANCE_IF_MAIN
const DB_MASTER
Definition defines.php:26