MediaWiki  REL1_31
runBatchedQuery.php
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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  $end = false;
91  }
92  if ( $prevEnd !== false ) {
93  $updateConds = array_merge( [ "$key > $prevEnd" ], $updateConds );
94  }
95 
96  $query = "UPDATE " . $dbw->tableName( $table ) .
97  " SET " . $set .
98  " WHERE " . $dbw->makeList( $updateConds, IDatabase::LIST_AND );
99 
100  $dbw->query( $query, __METHOD__ );
101 
102  $prevEnd = $end;
103 
104  $affected = $dbw->affectedRows();
105  $this->output( "$affected rows affected\n" );
106  wfWaitForSlaves();
107  } while ( $res->numRows() );
108  }
109 
110  public function getDbType() {
111  return Maintenance::DB_ADMIN;
112  }
113 }
114 
116 require_once RUN_MAINTENANCE_IF_MAIN;
$maintClass
$maintClass
Definition: runBatchedQuery.php:115
BatchedQueryRunner\getDbType
getDbType()
Does the script need different DB access? By default, we give Maintenance scripts normal rights to th...
Definition: runBatchedQuery.php:110
use
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
Definition: APACHE-LICENSE-2.0.txt:10
Maintenance\addDescription
addDescription( $text)
Set the description text.
Definition: Maintenance.php:291
BatchedQueryRunner\__construct
__construct()
Default constructor.
Definition: runBatchedQuery.php:36
RUN_MAINTENANCE_IF_MAIN
require_once RUN_MAINTENANCE_IF_MAIN
Definition: maintenance.txt:50
$res
$res
Definition: database.txt:21
Maintenance
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
Definition: maintenance.txt:39
BatchedQueryRunner\execute
execute()
Do the actual work.
Definition: runBatchedQuery.php:49
wfWaitForSlaves
wfWaitForSlaves( $ifWritesSince=null, $wiki=false, $cluster=false, $timeout=null)
Waits for the replica DBs to catch up to the master position.
Definition: GlobalFunctions.php:2966
php
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:37
LIST_AND
const LIST_AND
Definition: Defines.php:53
Wikimedia\Rdbms\IDatabase
Basic database interface for live and lazy-loaded relation database handles.
Definition: IDatabase.php:38
Maintenance\addOption
addOption( $name, $description, $required=false, $withArg=false, $shortName=false, $multiOccurrence=false)
Add a parameter to the script.
Definition: Maintenance.php:219
DB_MASTER
const DB_MASTER
Definition: defines.php:26
Maintenance\DB_ADMIN
const DB_ADMIN
Definition: Maintenance.php:68
MediaWiki\MediaWikiServices\getInstance
static getInstance()
Returns the global default instance of the top level service locator.
Definition: MediaWikiServices.php:109
BatchedQueryRunner
Maintenance script to run a database query in batches and wait for replica DBs.
Definition: runBatchedQuery.php:35
Maintenance\getOption
getOption( $name, $default=null)
Get an option, or return the default.
Definition: Maintenance.php:254
Maintenance\getDB
getDB( $db, $groups=[], $wiki=false)
Returns a database to be used by current maintenance script.
Definition: Maintenance.php:1309
Maintenance\output
output( $out, $channel=null)
Throw some output to the user.
Definition: Maintenance.php:388
class
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:56
$query
null for the 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:1620