3 * @defgroup Database Database
5 * This file deals with database interface functions
6 * and query specifics/optimisations.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 * http://www.gnu.org/copyleft/gpl.html
26 namespace Wikimedia\Rdbms
;
28 use Psr\Log\LoggerAwareInterface
;
29 use Psr\Log\LoggerInterface
;
30 use Psr\Log\NullLogger
;
31 use Wikimedia\ScopedCallback
;
32 use Wikimedia\Timestamp\ConvertibleTimestamp
;
37 use InvalidArgumentException
;
38 use UnexpectedValueException
;
43 * Relational database abstraction object
48 abstract class Database
implements IDatabase
, IMaintainableDatabase
, LoggerAwareInterface
{
49 /** Number of times to re-try an operation in case of deadlock */
50 const DEADLOCK_TRIES
= 4;
51 /** Minimum time to wait before retry, in microseconds */
52 const DEADLOCK_DELAY_MIN
= 500000;
53 /** Maximum time to wait before retry */
54 const DEADLOCK_DELAY_MAX
= 1500000;
56 /** How long before it is worth doing a dummy query to test the connection */
58 const PING_QUERY
= 'SELECT 1 AS ping';
60 const TINY_WRITE_SEC
= 0.010;
61 const SLOW_WRITE_SEC
= 0.500;
62 const SMALL_WRITE_ROWS
= 100;
64 /** @var string Lock granularity is on the level of the entire database */
65 const ATTR_DB_LEVEL_LOCKING
= 'db-level-locking';
66 /** @var string The SCHEMA keyword refers to a grouping of tables in a database */
67 const ATTR_SCHEMAS_AS_TABLE_GROUPS
= 'supports-schemas';
69 /** @var int New Database instance will not be connected yet when returned */
70 const NEW_UNCONNECTED
= 0;
71 /** @var int New Database instance will already be connected when returned */
72 const NEW_CONNECTED
= 1;
74 /** @var string SQL query */
75 protected $lastQuery = '';
76 /** @var float|bool UNIX timestamp of last write query */
77 protected $lastWriteTime = false;
78 /** @var string|bool */
79 protected $phpError = false;
80 /** @var string Server that this instance is currently connected to */
82 /** @var string User that this instance is currently connected under the name of */
84 /** @var string Password used to establish the current connection */
86 /** @var array[] Map of (table => (dbname, schema, prefix) map) */
87 protected $tableAliases = [];
88 /** @var string[] Map of (index alias => index) */
89 protected $indexAliases = [];
90 /** @var bool Whether this PHP instance is for a CLI script */
92 /** @var string Agent name for query profiling */
94 /** @var array Parameters used by initConnection() to establish a connection */
95 protected $connectionParams = [];
96 /** @var BagOStuff APC cache */
98 /** @var LoggerInterface */
99 protected $connLogger;
100 /** @var LoggerInterface */
101 protected $queryLogger;
102 /** @var callable Error logging callback */
103 protected $errorLogger;
104 /** @var callable Deprecation logging callback */
105 protected $deprecationLogger;
107 /** @var resource|null Database connection */
108 protected $conn = null;
110 protected $opened = false;
112 /** @var array[] List of (callable, method name, atomic section id) */
113 protected $trxIdleCallbacks = [];
114 /** @var array[] List of (callable, method name, atomic section id) */
115 protected $trxPreCommitCallbacks = [];
116 /** @var array[] List of (callable, method name, atomic section id) */
117 protected $trxEndCallbacks = [];
118 /** @var callable[] Map of (name => callable) */
119 protected $trxRecurringCallbacks = [];
120 /** @var bool Whether to suppress triggering of transaction end callbacks */
121 protected $trxEndCallbacksSuppressed = false;
126 protected $lbInfo = [];
127 /** @var array|bool */
128 protected $schemaVars = false;
130 protected $sessionVars = [];
131 /** @var array|null */
132 protected $preparedArgs;
133 /** @var string|bool|null Stashed value of html_errors INI setting */
134 protected $htmlErrors;
136 protected $delimiter = ';';
137 /** @var DatabaseDomain */
138 protected $currentDomain;
139 /** @var integer|null Rows affected by the last query to query() or its CRUD wrappers */
140 protected $affectedRowCount;
143 * @var int Transaction status
145 protected $trxStatus = self
::STATUS_TRX_NONE
;
147 * @var Exception|null The last error that caused the status to become STATUS_TRX_ERROR
149 protected $trxStatusCause;
151 * @var array|null If wasKnownStatementRollbackError() prevented trxStatus from being set,
152 * the relevant details are stored here.
154 protected $trxStatusIgnoredCause;
156 * Either 1 if a transaction is active or 0 otherwise.
157 * The other Trx fields may not be meaningfull if this is 0.
161 protected $trxLevel = 0;
163 * Either a short hexidecimal string if a transaction is active or ""
166 * @see Database::trxLevel
168 protected $trxShortId = '';
170 * The UNIX time that the transaction started. Callers can assume that if
171 * snapshot isolation is used, then the data is *at least* up to date to that
172 * point (possibly more up-to-date since the first SELECT defines the snapshot).
175 * @see Database::trxLevel
177 private $trxTimestamp = null;
178 /** @var float Lag estimate at the time of BEGIN */
179 private $trxReplicaLag = null;
181 * Remembers the function name given for starting the most recent transaction via begin().
182 * Used to provide additional context for error reporting.
185 * @see Database::trxLevel
187 private $trxFname = null;
189 * Record if possible write queries were done in the last transaction started
192 * @see Database::trxLevel
194 private $trxDoneWrites = false;
196 * Record if the current transaction was started implicitly due to DBO_TRX being set.
199 * @see Database::trxLevel
201 private $trxAutomatic = false;
203 * Counter for atomic savepoint identifiers. Reset when a new transaction begins.
207 private $trxAtomicCounter = 0;
209 * Array of levels of atomicity within transactions
211 * @var array List of (name, unique ID, savepoint ID)
213 private $trxAtomicLevels = [];
215 * Record if the current transaction was started implicitly by Database::startAtomic
219 private $trxAutomaticAtomic = false;
221 * Track the write query callers of the current transaction
225 private $trxWriteCallers = [];
227 * @var float Seconds spent in write queries for the current transaction
229 private $trxWriteDuration = 0.0;
231 * @var int Number of write queries for the current transaction
233 private $trxWriteQueryCount = 0;
235 * @var int Number of rows affected by write queries for the current transaction
237 private $trxWriteAffectedRows = 0;
239 * @var float Like trxWriteQueryCount but excludes lock-bound, easy to replicate, queries
241 private $trxWriteAdjDuration = 0.0;
243 * @var int Number of write queries counted in trxWriteAdjDuration
245 private $trxWriteAdjQueryCount = 0;
247 * @var float RTT time estimate
249 private $rttEstimate = 0.0;
251 /** @var array Map of (name => 1) for locks obtained via lock() */
252 private $namedLocksHeld = [];
253 /** @var array Map of (table name => 1) for TEMPORARY tables */
254 protected $sessionTempTables = [];
256 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
257 private $lazyMasterHandle;
259 /** @var float UNIX timestamp */
260 protected $lastPing = 0.0;
262 /** @var int[] Prior flags member variable values */
263 private $priorFlags = [];
265 /** @var callable|null */
267 /** @var TransactionProfiler */
268 protected $trxProfiler;
271 protected $nonNativeInsertSelectBatchSize = 10000;
273 /** @var string Idiom used when a cancelable atomic section started the transaction */
274 private static $NOT_APPLICABLE = 'n/a';
275 /** @var string Prefix to the atomic section counter used to make savepoint IDs */
276 private static $SAVEPOINT_PREFIX = 'wikimedia_rdbms_atomic';
278 /** @var int Transaction is in a error state requiring a full or savepoint rollback */
279 const STATUS_TRX_ERROR
= 1;
280 /** @var int Transaction is active and in a normal state */
281 const STATUS_TRX_OK
= 2;
282 /** @var int No transaction is active */
283 const STATUS_TRX_NONE
= 3;
285 /** @var int Writes to this temporary table do not affect lastDoneWrites() */
286 const TEMP_NORMAL
= 1;
287 /** @var int Writes to this temporary table effect lastDoneWrites() */
288 const TEMP_PSEUDO_PERMANENT
= 2;
291 * @note exceptions for missing libraries/drivers should be thrown in initConnection()
292 * @param array $params Parameters passed from Database::factory()
294 protected function __construct( array $params ) {
295 foreach ( [ 'host', 'user', 'password', 'dbname', 'schema', 'tablePrefix' ] as $name ) {
296 $this->connectionParams
[$name] = $params[$name];
299 $this->cliMode
= $params['cliMode'];
300 // Agent name is added to SQL queries in a comment, so make sure it can't break out
301 $this->agent
= str_replace( '/', '-', $params['agent'] );
303 $this->flags
= $params['flags'];
304 if ( $this->flags
& self
::DBO_DEFAULT
) {
305 if ( $this->cliMode
) {
306 $this->flags
&= ~self
::DBO_TRX
;
308 $this->flags |
= self
::DBO_TRX
;
311 // Disregard deprecated DBO_IGNORE flag (T189999)
312 $this->flags
&= ~self
::DBO_IGNORE
;
314 $this->sessionVars
= $params['variables'];
316 $this->srvCache
= $params['srvCache'] ??
new HashBagOStuff();
318 $this->profiler
= is_callable( $params['profiler'] ) ?
$params['profiler'] : null;
319 $this->trxProfiler
= $params['trxProfiler'];
320 $this->connLogger
= $params['connLogger'];
321 $this->queryLogger
= $params['queryLogger'];
322 $this->errorLogger
= $params['errorLogger'];
323 $this->deprecationLogger
= $params['deprecationLogger'];
325 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
326 $this->nonNativeInsertSelectBatchSize
= $params['nonNativeInsertSelectBatchSize'];
329 // Set initial dummy domain until open() sets the final DB/prefix
330 $this->currentDomain
= new DatabaseDomain(
331 $params['dbname'] != '' ?
$params['dbname'] : null,
332 $params['schema'] != '' ?
$params['schema'] : null,
333 $params['tablePrefix']
338 * Initialize the connection to the database over the wire (or to local files)
340 * @throws LogicException
341 * @throws InvalidArgumentException
342 * @throws DBConnectionError
345 final public function initConnection() {
346 if ( $this->isOpen() ) {
347 throw new LogicException( __METHOD__
. ': already connected.' );
349 // Establish the connection
350 $this->doInitConnection();
354 * Actually connect to the database over the wire (or to local files)
356 * @throws InvalidArgumentException
357 * @throws DBConnectionError
360 protected function doInitConnection() {
361 if ( strlen( $this->connectionParams
['user'] ) ) {
363 $this->connectionParams
['host'],
364 $this->connectionParams
['user'],
365 $this->connectionParams
['password'],
366 $this->connectionParams
['dbname'],
367 $this->connectionParams
['schema'],
368 $this->connectionParams
['tablePrefix']
371 throw new InvalidArgumentException( "No database user provided." );
376 * Open a new connection to the database (closing any existing one)
378 * @param string $server Database server host
379 * @param string $user Database user name
380 * @param string $password Database user password
381 * @param string $dbName Database name
382 * @param string|null $schema Database schema name
383 * @param string $tablePrefix Table prefix
385 * @throws DBConnectionError
387 abstract protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix );
390 * Construct a Database subclass instance given a database type and parameters
392 * This also connects to the database immediately upon object construction
394 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
395 * @param array $p Parameter map with keys:
396 * - host : The hostname of the DB server
397 * - user : The name of the database user the client operates under
398 * - password : The password for the database user
399 * - dbname : The name of the database to use where queries do not specify one.
400 * The database must exist or an error might be thrown. Setting this to the empty string
401 * will avoid any such errors and make the handle have no implicit database scope. This is
402 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
403 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
404 * in which user names and such are defined, e.g. users are database-specific in Postgres.
405 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
406 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
407 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
408 * recognized in queries. This can be used in place of schemas for handle site farms.
409 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
410 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
411 * flag in place UNLESS this this database simply acts as a key/value store.
412 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
413 * 'mysqli' driver; the old one 'mysql' has been removed.
414 * - variables: Optional map of session variables to set after connecting. This can be
415 * used to adjust lock timeouts or encoding modes and the like.
416 * - connLogger: Optional PSR-3 logger interface instance.
417 * - queryLogger: Optional PSR-3 logger interface instance.
418 * - profiler : Optional callback that takes a section name argument and returns
419 * a ScopedCallback instance that ends the profile section in its destructor.
420 * These will be called in query(), using a simplified version of the SQL that
421 * also includes the agent as a SQL comment.
422 * - trxProfiler: Optional TransactionProfiler instance.
423 * - errorLogger: Optional callback that takes an Exception and logs it.
424 * - deprecationLogger: Optional callback that takes a string and logs it.
425 * - cliMode: Whether to consider the execution context that of a CLI script.
426 * - agent: Optional name used to identify the end-user in query profiling/logging.
427 * - srvCache: Optional BagOStuff instance to an APC-style cache.
428 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
429 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
430 * @return Database|null If the database driver or extension cannot be found
431 * @throws InvalidArgumentException If the database driver or extension cannot be found
434 final public static function factory( $dbType, $p = [], $connect = self
::NEW_CONNECTED
) {
435 $class = self
::getClass( $dbType, $p['driver'] ??
null );
437 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
438 // Resolve some defaults for b/c
439 $p['host'] = $p['host'] ??
false;
440 $p['user'] = $p['user'] ??
false;
441 $p['password'] = $p['password'] ??
false;
442 $p['dbname'] = $p['dbname'] ??
false;
443 $p['flags'] = $p['flags'] ??
0;
444 $p['variables'] = $p['variables'] ??
[];
445 $p['tablePrefix'] = $p['tablePrefix'] ??
'';
446 $p['schema'] = $p['schema'] ??
null;
447 $p['cliMode'] = $p['cliMode'] ??
( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' );
448 $p['agent'] = $p['agent'] ??
'';
449 if ( !isset( $p['connLogger'] ) ) {
450 $p['connLogger'] = new NullLogger();
452 if ( !isset( $p['queryLogger'] ) ) {
453 $p['queryLogger'] = new NullLogger();
455 $p['profiler'] = $p['profiler'] ??
null;
456 if ( !isset( $p['trxProfiler'] ) ) {
457 $p['trxProfiler'] = new TransactionProfiler();
459 if ( !isset( $p['errorLogger'] ) ) {
460 $p['errorLogger'] = function ( Exception
$e ) {
461 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
464 if ( !isset( $p['deprecationLogger'] ) ) {
465 $p['deprecationLogger'] = function ( $msg ) {
466 trigger_error( $msg, E_USER_DEPRECATED
);
470 /** @var Database $conn */
471 $conn = new $class( $p );
472 if ( $connect == self
::NEW_CONNECTED
) {
473 $conn->initConnection();
483 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
484 * @param string|null $driver Optional name of a specific DB client driver
485 * @return array Map of (Database::ATTR_* constant => value) for all such constants
486 * @throws InvalidArgumentException
489 final public static function attributesFromType( $dbType, $driver = null ) {
491 self
::ATTR_DB_LEVEL_LOCKING
=> false,
492 self
::ATTR_SCHEMAS_AS_TABLE_GROUPS
=> false
495 $class = self
::getClass( $dbType, $driver );
497 return call_user_func( [ $class, 'getAttributes' ] ) +
$defaults;
501 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
502 * @param string|null $driver Optional name of a specific DB client driver
503 * @return string Database subclass name to use
504 * @throws InvalidArgumentException
506 private static function getClass( $dbType, $driver = null ) {
507 // For database types with built-in support, the below maps type to IDatabase
508 // implementations. For types with multipe driver implementations (PHP extensions),
509 // an array can be used, keyed by extension name. In case of an array, the
510 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
511 // we auto-detect the first available driver. For types without built-in support,
512 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
513 static $builtinTypes = [
514 'mssql' => DatabaseMssql
::class,
515 'mysql' => [ 'mysqli' => DatabaseMysqli
::class ],
516 'sqlite' => DatabaseSqlite
::class,
517 'postgres' => DatabasePostgres
::class,
520 $dbType = strtolower( $dbType );
523 if ( isset( $builtinTypes[$dbType] ) ) {
524 $possibleDrivers = $builtinTypes[$dbType];
525 if ( is_string( $possibleDrivers ) ) {
526 $class = $possibleDrivers;
527 } elseif ( (string)$driver !== '' ) {
528 if ( !isset( $possibleDrivers[$driver] ) ) {
529 throw new InvalidArgumentException( __METHOD__
.
530 " type '$dbType' does not support driver '{$driver}'" );
533 $class = $possibleDrivers[$driver];
535 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
536 if ( extension_loaded( $posDriver ) ) {
537 $class = $possibleClass;
543 $class = 'Database' . ucfirst( $dbType );
546 if ( $class === false ) {
547 throw new InvalidArgumentException( __METHOD__
.
548 " no viable database extension found for type '$dbType'" );
555 * @return array Map of (Database::ATTR_* constant => value
558 protected static function getAttributes() {
563 * Set the PSR-3 logger interface to use for query logging. (The logger
564 * interfaces for connection logging and error logging can be set with the
567 * @param LoggerInterface $logger
569 public function setLogger( LoggerInterface
$logger ) {
570 $this->queryLogger
= $logger;
573 public function getServerInfo() {
574 return $this->getServerVersion();
577 public function bufferResults( $buffer = null ) {
578 $res = !$this->getFlag( self
::DBO_NOBUFFER
);
579 if ( $buffer !== null ) {
581 ?
$this->clearFlag( self
::DBO_NOBUFFER
)
582 : $this->setFlag( self
::DBO_NOBUFFER
);
588 public function trxLevel() {
589 return $this->trxLevel
;
592 public function trxTimestamp() {
593 return $this->trxLevel ?
$this->trxTimestamp
: null;
597 * @return int One of the STATUS_TRX_* class constants
600 public function trxStatus() {
601 return $this->trxStatus
;
604 public function tablePrefix( $prefix = null ) {
605 $old = $this->currentDomain
->getTablePrefix();
606 if ( $prefix !== null ) {
607 $this->currentDomain
= new DatabaseDomain(
608 $this->currentDomain
->getDatabase(),
609 $this->currentDomain
->getSchema(),
617 public function dbSchema( $schema = null ) {
618 if ( strlen( $schema ) && $this->getDBname() === null ) {
619 throw new DBUnexpectedError( $this, "Cannot set schema to '$schema'; no database set." );
622 $old = $this->currentDomain
->getSchema();
623 if ( $schema !== null ) {
624 $this->currentDomain
= new DatabaseDomain(
625 $this->currentDomain
->getDatabase(),
626 // DatabaseDomain uses null for unspecified schemas
627 strlen( $schema ) ?
$schema : null,
628 $this->currentDomain
->getTablePrefix()
636 * @return string Schema to use to qualify relations in queries
638 protected function relationSchemaQualifier() {
639 return $this->dbSchema();
642 public function getLBInfo( $name = null ) {
643 if ( is_null( $name ) ) {
644 return $this->lbInfo
;
647 if ( array_key_exists( $name, $this->lbInfo
) ) {
648 return $this->lbInfo
[$name];
654 public function setLBInfo( $name, $value = null ) {
655 if ( is_null( $value ) ) {
656 $this->lbInfo
= $name;
658 $this->lbInfo
[$name] = $value;
662 public function setLazyMasterHandle( IDatabase
$conn ) {
663 $this->lazyMasterHandle
= $conn;
667 * @return IDatabase|null
668 * @see setLazyMasterHandle()
671 protected function getLazyMasterHandle() {
672 return $this->lazyMasterHandle
;
675 public function implicitGroupby() {
679 public function implicitOrderby() {
683 public function lastQuery() {
684 return $this->lastQuery
;
687 public function doneWrites() {
688 return (bool)$this->lastWriteTime
;
691 public function lastDoneWrites() {
692 return $this->lastWriteTime ?
: false;
695 public function writesPending() {
696 return $this->trxLevel
&& $this->trxDoneWrites
;
699 public function writesOrCallbacksPending() {
700 return $this->trxLevel
&& (
701 $this->trxDoneWrites ||
702 $this->trxIdleCallbacks ||
703 $this->trxPreCommitCallbacks ||
704 $this->trxEndCallbacks
708 public function preCommitCallbacksPending() {
709 return $this->trxLevel
&& $this->trxPreCommitCallbacks
;
713 * @return string|null
715 final protected function getTransactionRoundId() {
716 // If transaction round participation is enabled, see if one is active
717 if ( $this->getFlag( self
::DBO_TRX
) ) {
718 $id = $this->getLBInfo( 'trxRoundId' );
720 return is_string( $id ) ?
$id : null;
726 public function pendingWriteQueryDuration( $type = self
::ESTIMATE_TOTAL
) {
727 if ( !$this->trxLevel
) {
729 } elseif ( !$this->trxDoneWrites
) {
734 case self
::ESTIMATE_DB_APPLY
:
735 return $this->pingAndCalculateLastTrxApplyTime();
736 default: // everything
737 return $this->trxWriteDuration
;
742 * @return float Time to apply writes to replicas based on trxWrite* fields
744 private function pingAndCalculateLastTrxApplyTime() {
747 $rttAdjTotal = $this->trxWriteAdjQueryCount
* $rtt;
748 $applyTime = max( $this->trxWriteAdjDuration
- $rttAdjTotal, 0 );
749 // For omitted queries, make them count as something at least
750 $omitted = $this->trxWriteQueryCount
- $this->trxWriteAdjQueryCount
;
751 $applyTime +
= self
::TINY_WRITE_SEC
* $omitted;
756 public function pendingWriteCallers() {
757 return $this->trxLevel ?
$this->trxWriteCallers
: [];
760 public function pendingWriteRowsAffected() {
761 return $this->trxWriteAffectedRows
;
765 * List the methods that have write queries or callbacks for the current transaction
767 * This method should not be used outside of Database/LoadBalancer
772 public function pendingWriteAndCallbackCallers() {
773 $fnames = $this->pendingWriteCallers();
775 $this->trxIdleCallbacks
,
776 $this->trxPreCommitCallbacks
,
777 $this->trxEndCallbacks
779 foreach ( $callbacks as $callback ) {
780 $fnames[] = $callback[1];
790 private function flatAtomicSectionList() {
791 return array_reduce( $this->trxAtomicLevels
, function ( $accum, $v ) {
792 return $accum === null ?
$v[0] : "$accum, " . $v[0];
796 public function isOpen() {
797 return $this->opened
;
800 public function setFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
801 if ( ( $flag & self
::DBO_IGNORE
) ) {
802 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
805 if ( $remember === self
::REMEMBER_PRIOR
) {
806 array_push( $this->priorFlags
, $this->flags
);
808 $this->flags |
= $flag;
811 public function clearFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
812 if ( ( $flag & self
::DBO_IGNORE
) ) {
813 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
816 if ( $remember === self
::REMEMBER_PRIOR
) {
817 array_push( $this->priorFlags
, $this->flags
);
819 $this->flags
&= ~
$flag;
822 public function restoreFlags( $state = self
::RESTORE_PRIOR
) {
823 if ( !$this->priorFlags
) {
827 if ( $state === self
::RESTORE_INITIAL
) {
828 $this->flags
= reset( $this->priorFlags
);
829 $this->priorFlags
= [];
831 $this->flags
= array_pop( $this->priorFlags
);
835 public function getFlag( $flag ) {
836 return (bool)( $this->flags
& $flag );
840 * @param string $name Class field name
842 * @deprecated Since 1.28
844 public function getProperty( $name ) {
848 public function getDomainID() {
849 return $this->currentDomain
->getId();
852 final public function getWikiID() {
853 return $this->getDomainID();
857 * Get information about an index into an object
858 * @param string $table Table name
859 * @param string $index Index name
860 * @param string $fname Calling function name
861 * @return mixed Database-specific index description class or false if the index does not exist
863 abstract function indexInfo( $table, $index, $fname = __METHOD__
);
866 * Wrapper for addslashes()
868 * @param string $s String to be slashed.
869 * @return string Slashed string.
871 abstract function strencode( $s );
874 * Set a custom error handler for logging errors during database connection
876 protected function installErrorHandler() {
877 $this->phpError
= false;
878 $this->htmlErrors
= ini_set( 'html_errors', '0' );
879 set_error_handler( [ $this, 'connectionErrorLogger' ] );
883 * Restore the previous error handler and return the last PHP error for this DB
885 * @return bool|string
887 protected function restoreErrorHandler() {
888 restore_error_handler();
889 if ( $this->htmlErrors
!== false ) {
890 ini_set( 'html_errors', $this->htmlErrors
);
893 return $this->getLastPHPError();
897 * @return string|bool Last PHP error for this DB (typically connection errors)
899 protected function getLastPHPError() {
900 if ( $this->phpError
) {
901 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->phpError
);
902 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
911 * Error handler for logging errors during database connection
912 * This method should not be used outside of Database classes
915 * @param string $errstr
917 public function connectionErrorLogger( $errno, $errstr ) {
918 $this->phpError
= $errstr;
922 * Create a log context to pass to PSR-3 logger functions.
924 * @param array $extras Additional data to add to context
927 protected function getLogContext( array $extras = [] ) {
930 'db_server' => $this->server
,
931 'db_name' => $this->getDBname(),
932 'db_user' => $this->user
,
938 final public function close() {
939 $exception = null; // error to throw after disconnecting
941 $wasOpen = $this->opened
;
942 // This should mostly do nothing if the connection is already closed
944 // Roll back any dangling transaction first
945 if ( $this->trxLevel
) {
946 if ( $this->trxAtomicLevels
) {
947 // Cannot let incomplete atomic sections be committed
948 $levels = $this->flatAtomicSectionList();
949 $exception = new DBUnexpectedError(
951 __METHOD__
. ": atomic sections $levels are still open."
953 } elseif ( $this->trxAutomatic
) {
954 // Only the connection manager can commit non-empty DBO_TRX transactions
955 // (empty ones we can silently roll back)
956 if ( $this->writesOrCallbacksPending() ) {
957 $exception = new DBUnexpectedError(
960 ": mass commit/rollback of peer transaction required (DBO_TRX set)."
964 // Manual transactions should have been committed or rolled
965 // back, even if empty.
966 $exception = new DBUnexpectedError(
968 __METHOD__
. ": transaction is still open (from {$this->trxFname})."
972 if ( $this->trxEndCallbacksSuppressed
) {
973 $exception = $exception ?
: new DBUnexpectedError(
975 __METHOD__
. ': callbacks are suppressed; cannot properly commit.'
979 // Rollback the changes and run any callbacks as needed
980 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
983 // Close the actual connection in the binding handle
984 $closed = $this->closeConnection();
986 $closed = true; // already closed; nothing to do
990 $this->opened
= false;
992 // Throw any unexpected errors after having disconnected
993 if ( $exception instanceof Exception
) {
997 // Note that various subclasses call close() at the start of open(), which itself is
998 // called by replaceLostConnection(). In that case, just because onTransactionResolution()
999 // callbacks are pending does not mean that an exception should be thrown. Rather, they
1000 // will be executed after the reconnection step.
1002 // Sanity check that no callbacks are dangling
1003 $fnames = $this->pendingWriteAndCallbackCallers();
1005 throw new RuntimeException(
1006 "Transaction callbacks are still pending:\n" . implode( ', ', $fnames )
1015 * Make sure there is an open connection handle (alive or not) as a sanity check
1017 * This guards against fatal errors to the binding handle not being defined
1018 * in cases where open() was never called or close() was already called
1020 * @throws DBUnexpectedError
1022 protected function assertHasConnectionHandle() {
1023 if ( !$this->isOpen() ) {
1024 throw new DBUnexpectedError( $this, "DB connection was already closed." );
1029 * Make sure that this server is not marked as a replica nor read-only as a sanity check
1031 * @throws DBUnexpectedError
1033 protected function assertIsWritableMaster() {
1034 if ( $this->getLBInfo( 'replica' ) === true ) {
1035 throw new DBReadOnlyRoleError(
1037 'Write operations are not allowed on replica database connections.'
1040 $reason = $this->getReadOnlyReason();
1041 if ( $reason !== false ) {
1042 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
1047 * Closes underlying database connection
1049 * @return bool Whether connection was closed successfully
1051 abstract protected function closeConnection();
1054 * @deprecated since 1.32
1055 * @param string $error Fallback message, if none is given by DB
1056 * @throws DBConnectionError
1058 public function reportConnectionError( $error = 'Unknown error' ) {
1059 call_user_func( $this->deprecationLogger
, 'Use of ' . __METHOD__
. ' is deprecated.' );
1060 throw new DBConnectionError( $this, $this->lastError() ?
: $error );
1064 * Run a query and return a DBMS-dependent wrapper or boolean
1066 * For SELECT queries, this returns either:
1067 * - a) A driver-specific value/resource, only on success. This can be iterated
1068 * over by calling fetchObject()/fetchRow() until there are no more rows.
1069 * Alternatively, the result can be passed to resultObject() to obtain a
1070 * ResultWrapper instance which can then be iterated over via "foreach".
1071 * - b) False, on any query failure
1073 * For non-SELECT queries, this returns either:
1074 * - a) A driver-specific value/resource, only on success
1075 * - b) True, only on success (e.g. no meaningful result other than "OK")
1076 * - c) False, on any query failure
1078 * @param string $sql SQL query
1079 * @return mixed|bool An object, resource, or true on success; false on failure
1081 abstract protected function doQuery( $sql );
1084 * Determine whether a query writes to the DB. When in doubt, this returns true.
1088 * - Subsequent web requests should not need to wait for replication from
1089 * the master position seen by this web request, unless this request made
1090 * changes to the master. This is handled by ChronologyProtector by checking
1091 * doneWrites() at the end of the request. doneWrites() returns true if any
1092 * query set lastWriteTime; which query() does based on isWriteQuery().
1094 * - Reject write queries to replica DBs, in query().
1096 * @param string $sql
1099 protected function isWriteQuery( $sql ) {
1100 // BEGIN and COMMIT queries are considered read queries here.
1101 // Database backends and drivers (MySQL, MariaDB, php-mysqli) generally
1102 // treat these as write queries, in that their results have "affected rows"
1103 // as meta data as from writes, instead of "num rows" as from reads.
1104 // But, we treat them as read queries because when reading data (from
1105 // either replica or master) we use transactions to enable repeatable-read
1106 // snapshots, which ensures we get consistent results from the same snapshot
1107 // for all queries within a request. Use cases:
1108 // - Treating these as writes would trigger ChronologyProtector (see method doc).
1109 // - We use this method to reject writes to replicas, but we need to allow
1110 // use of transactions on replicas for read snapshots. This fine given
1111 // that transactions by themselves don't make changes, only actual writes
1112 // within the transaction matter, which we still detect.
1114 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SAVEPOINT|RELEASE|SET|SHOW|EXPLAIN|\(SELECT)\b/i',
1120 * @param string $sql
1121 * @return string|null
1123 protected function getQueryVerb( $sql ) {
1124 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ?
strtoupper( $m[1] ) : null;
1128 * Determine whether a SQL statement is sensitive to isolation level.
1130 * A SQL statement is considered transactable if its result could vary
1131 * depending on the transaction isolation level. Operational commands
1132 * such as 'SET' and 'SHOW' are not considered to be transactable.
1134 * Main purpose: Used by query() to decide whether to begin a transaction
1135 * before the current query (in DBO_TRX mode, on by default).
1137 * @param string $sql
1140 protected function isTransactableQuery( $sql ) {
1142 $this->getQueryVerb( $sql ),
1143 [ 'BEGIN', 'ROLLBACK', 'COMMIT', 'SET', 'SHOW', 'CREATE', 'ALTER' ],
1149 * @param string $sql A SQL query
1150 * @param bool $pseudoPermanent Treat any table from CREATE TEMPORARY as pseudo-permanent
1151 * @return int|null A self::TEMP_* constant for temp table operations or null otherwise
1153 protected function registerTempTableWrite( $sql, $pseudoPermanent ) {
1154 static $qt = '[`"\']?(\w+)[`"\']?'; // quoted table
1157 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?' . $qt . '/i',
1161 $type = $pseudoPermanent ? self
::TEMP_PSEUDO_PERMANENT
: self
::TEMP_NORMAL
;
1162 $this->sessionTempTables
[$matches[1]] = $type;
1165 } elseif ( preg_match(
1166 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?' . $qt . '/i',
1170 $type = $this->sessionTempTables
[$matches[1]] ??
null;
1171 unset( $this->sessionTempTables
[$matches[1]] );
1174 } elseif ( preg_match(
1175 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?' . $qt . '/i',
1179 return $this->sessionTempTables
[$matches[1]] ??
null;
1180 } elseif ( preg_match(
1181 '/^(?:(?:INSERT|REPLACE)\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+' . $qt . '/i',
1185 return $this->sessionTempTables
[$matches[1]] ??
null;
1191 public function query( $sql, $fname = __METHOD__
, $flags = 0 ) {
1192 $this->assertTransactionStatus( $sql, $fname );
1193 $this->assertHasConnectionHandle();
1195 $flags = (int)$flags; // b/c; this field used to be a bool
1196 $ignoreErrors = $this->hasFlags( $flags, self
::QUERY_SILENCE_ERRORS
);
1198 $priorTransaction = $this->trxLevel
;
1199 $priorWritesPending = $this->writesOrCallbacksPending();
1200 $this->lastQuery
= $sql;
1202 if ( $this->isWriteQuery( $sql ) ) {
1203 # In theory, non-persistent writes are allowed in read-only mode, but due to things
1204 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1205 $this->assertIsWritableMaster();
1206 # Do not treat temporary table writes as "meaningful writes" that need committing.
1207 # Profile them as reads. Integration tests can override this behavior via $flags.
1208 $pseudoPermanent = $this->hasFlags( $flags, self
::QUERY_PSEUDO_PERMANENT
);
1209 $tableType = $this->registerTempTableWrite( $sql, $pseudoPermanent );
1210 $isEffectiveWrite = ( $tableType !== self
::TEMP_NORMAL
);
1211 # DBConnRef uses QUERY_REPLICA_ROLE to enforce the replica role for raw SQL queries
1212 if ( $isEffectiveWrite && $this->hasFlags( $flags, self
::QUERY_REPLICA_ROLE
) ) {
1213 throw new DBReadOnlyRoleError( $this, "Cannot write; target role is DB_REPLICA" );
1216 $isEffectiveWrite = false;
1219 # Add trace comment to the begin of the sql string, right after the operator.
1220 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1221 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1223 # Send the query to the server and fetch any corresponding errors
1224 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1225 $lastError = $this->lastError();
1226 $lastErrno = $this->lastErrno();
1228 $recoverableSR = false; // recoverable statement rollback?
1229 $recoverableCL = false; // recoverable connection loss?
1231 if ( $ret === false && $this->wasConnectionLoss() ) {
1232 # Check if no meaningful session state was lost
1233 $recoverableCL = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1234 # Update session state tracking and try to restore the connection
1235 $reconnected = $this->replaceLostConnection( __METHOD__
);
1236 # Silently resend the query to the server if it is safe and possible
1237 if ( $recoverableCL && $reconnected ) {
1238 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1239 $lastError = $this->lastError();
1240 $lastErrno = $this->lastErrno();
1242 if ( $ret === false && $this->wasConnectionLoss() ) {
1243 # Query probably causes disconnects; reconnect and do not re-run it
1244 $this->replaceLostConnection( __METHOD__
);
1246 $recoverableCL = false; // connection does not need recovering
1247 $recoverableSR = $this->wasKnownStatementRollbackError();
1251 $recoverableSR = $this->wasKnownStatementRollbackError();
1254 if ( $ret === false ) {
1255 if ( $priorTransaction ) {
1256 if ( $recoverableSR ) {
1257 # We're ignoring an error that caused just the current query to be aborted.
1258 # But log the cause so we can log a deprecation notice if a caller actually
1260 $this->trxStatusIgnoredCause
= [ $lastError, $lastErrno, $fname ];
1261 } elseif ( !$recoverableCL ) {
1262 # Either the query was aborted or all queries after BEGIN where aborted.
1263 # In the first case, the only options going forward are (a) ROLLBACK, or
1264 # (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
1265 # option is ROLLBACK, since the snapshots would have been released.
1266 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
1267 $this->trxStatusCause
=
1268 $this->getQueryExceptionAndLog( $lastError, $lastErrno, $sql, $fname );
1269 $ignoreErrors = false; // cannot recover
1270 $this->trxStatusIgnoredCause
= null;
1274 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $ignoreErrors );
1277 return $this->resultObject( $ret );
1281 * Wrapper for query() that also handles profiling, logging, and affected row count updates
1283 * @param string $sql Original SQL query
1284 * @param string $commentedSql SQL query with debugging/trace comment
1285 * @param bool $isEffectiveWrite Whether the query is a (non-temporary table) write
1286 * @param string $fname Name of the calling function
1287 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1288 * object for a successful read query, or false on failure
1290 private function attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname ) {
1291 $this->beginIfImplied( $sql, $fname );
1293 # Keep track of whether the transaction has write queries pending
1294 if ( $isEffectiveWrite ) {
1295 $this->lastWriteTime
= microtime( true );
1296 if ( $this->trxLevel
&& !$this->trxDoneWrites
) {
1297 $this->trxDoneWrites
= true;
1298 $this->trxProfiler
->transactionWritingIn(
1299 $this->server
, $this->getDomainID(), $this->trxShortId
);
1303 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
1304 $this->queryLogger
->debug( "{$this->getDomainID()} {$commentedSql}" );
1307 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1308 # generalizeSQL() will probably cut down the query to reasonable
1309 # logging size most of the time. The substr is really just a sanity check.
1311 $queryProf = 'query-m: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1313 $queryProf = 'query: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1316 # Include query transaction state
1317 $queryProf .= $this->trxShortId ?
" [TRX#{$this->trxShortId}]" : "";
1319 $startTime = microtime( true );
1320 $ps = $this->profiler ?
( $this->profiler
)( $queryProf ) : null;
1321 $this->affectedRowCount
= null;
1322 $ret = $this->doQuery( $commentedSql );
1323 $this->affectedRowCount
= $this->affectedRows();
1324 unset( $ps ); // profile out (if set)
1325 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1327 if ( $ret !== false ) {
1328 $this->lastPing
= $startTime;
1329 if ( $isEffectiveWrite && $this->trxLevel
) {
1330 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1331 $this->trxWriteCallers
[] = $fname;
1335 if ( $sql === self
::PING_QUERY
) {
1336 $this->rttEstimate
= $queryRuntime;
1339 $this->trxProfiler
->recordQueryCompletion(
1343 $isEffectiveWrite ?
$this->affectedRows() : $this->numRows( $ret )
1345 $this->queryLogger
->debug( $sql, [
1347 'master' => $isMaster,
1348 'runtime' => $queryRuntime,
1355 * Start an implicit transaction if DBO_TRX is enabled and no transaction is active
1357 * @param string $sql
1358 * @param string $fname
1360 private function beginIfImplied( $sql, $fname ) {
1363 $this->getFlag( self
::DBO_TRX
) &&
1364 $this->isTransactableQuery( $sql )
1366 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
1367 $this->trxAutomatic
= true;
1372 * Update the estimated run-time of a query, not counting large row lock times
1374 * LoadBalancer can be set to rollback transactions that will create huge replication
1375 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1376 * queries, like inserting a row can take a long time due to row locking. This method
1377 * uses some simple heuristics to discount those cases.
1379 * @param string $sql A SQL write query
1380 * @param float $runtime Total runtime, including RTT
1381 * @param int $affected Affected row count
1383 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1384 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1385 $indicativeOfReplicaRuntime = true;
1386 if ( $runtime > self
::SLOW_WRITE_SEC
) {
1387 $verb = $this->getQueryVerb( $sql );
1388 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1389 if ( $verb === 'INSERT' ) {
1390 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
;
1391 } elseif ( $verb === 'REPLACE' ) {
1392 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
/ 2;
1396 $this->trxWriteDuration +
= $runtime;
1397 $this->trxWriteQueryCount +
= 1;
1398 $this->trxWriteAffectedRows +
= $affected;
1399 if ( $indicativeOfReplicaRuntime ) {
1400 $this->trxWriteAdjDuration +
= $runtime;
1401 $this->trxWriteAdjQueryCount +
= 1;
1406 * Error out if the DB is not in a valid state for a query via query()
1408 * @param string $sql
1409 * @param string $fname
1410 * @throws DBTransactionStateError
1412 private function assertTransactionStatus( $sql, $fname ) {
1413 $verb = $this->getQueryVerb( $sql );
1414 if ( $verb === 'USE' ) {
1415 throw new DBUnexpectedError( $this, "Got USE query; use selectDomain() instead." );
1418 if ( $verb === 'ROLLBACK' ) { // transaction/savepoint
1422 if ( $this->trxStatus
< self
::STATUS_TRX_OK
) {
1423 throw new DBTransactionStateError(
1425 "Cannot execute query from $fname while transaction status is ERROR.",
1427 $this->trxStatusCause
1429 } elseif ( $this->trxStatus
=== self
::STATUS_TRX_OK
&& $this->trxStatusIgnoredCause
) {
1430 list( $iLastError, $iLastErrno, $iFname ) = $this->trxStatusIgnoredCause
;
1431 call_user_func( $this->deprecationLogger
,
1432 "Caller from $fname ignored an error originally raised from $iFname: " .
1433 "[$iLastErrno] $iLastError"
1435 $this->trxStatusIgnoredCause
= null;
1439 public function assertNoOpenTransactions() {
1440 if ( $this->explicitTrxActive() ) {
1441 throw new DBTransactionError(
1443 "Explicit transaction still active. A caller may have caught an error. "
1444 . "Open transactions: " . $this->flatAtomicSectionList()
1450 * Determine whether it is safe to retry queries after a database connection is lost
1452 * @param string $sql SQL query
1453 * @param bool $priorWritesPending Whether there is a transaction open with
1454 * possible write queries or transaction pre-commit/idle callbacks
1455 * waiting on it to finish.
1456 * @return bool True if it is safe to retry the query, false otherwise
1458 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1459 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1460 # Dropped connections also mean that named locks are automatically released.
1461 # Only allow error suppression in autocommit mode or when the lost transaction
1462 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1463 if ( $this->namedLocksHeld
) {
1464 return false; // possible critical section violation
1465 } elseif ( $this->sessionTempTables
) {
1466 return false; // tables might be queried latter
1467 } elseif ( $sql === 'COMMIT' ) {
1468 return !$priorWritesPending; // nothing written anyway? (T127428)
1469 } elseif ( $sql === 'ROLLBACK' ) {
1470 return true; // transaction lost...which is also what was requested :)
1471 } elseif ( $this->explicitTrxActive() ) {
1472 return false; // don't drop atomocity and explicit snapshots
1473 } elseif ( $priorWritesPending ) {
1474 return false; // prior writes lost from implicit transaction
1481 * Clean things up after session (and thus transaction) loss before reconnect
1483 private function handleSessionLossPreconnect() {
1484 // Clean up tracking of session-level things...
1485 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1486 // https://www.postgresql.org/docs/9.2/static/sql-createtable.html (ignoring ON COMMIT)
1487 $this->sessionTempTables
= [];
1488 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1489 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1490 $this->namedLocksHeld
= [];
1491 // Session loss implies transaction loss
1492 $this->trxLevel
= 0;
1493 $this->trxAtomicCounter
= 0;
1494 $this->trxIdleCallbacks
= []; // T67263; transaction already lost
1495 $this->trxPreCommitCallbacks
= []; // T67263; transaction already lost
1496 // @note: leave trxRecurringCallbacks in place
1497 if ( $this->trxDoneWrites
) {
1498 $this->trxProfiler
->transactionWritingOut(
1500 $this->getDomainID(),
1502 $this->pendingWriteQueryDuration( self
::ESTIMATE_TOTAL
),
1503 $this->trxWriteAffectedRows
1509 * Clean things up after session (and thus transaction) loss after reconnect
1511 private function handleSessionLossPostconnect() {
1513 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1514 // If callback suppression is set then the array will remain unhandled.
1515 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1516 } catch ( Exception
$ex ) {
1517 // Already logged; move on...
1520 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1521 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1522 } catch ( Exception
$ex ) {
1523 // Already logged; move on...
1528 * Checks whether the cause of the error is detected to be a timeout.
1530 * It returns false by default, and not all engines support detecting this yet.
1531 * If this returns false, it will be treated as a generic query error.
1533 * @param string $error Error text
1534 * @param int $errno Error number
1537 protected function wasQueryTimeout( $error, $errno ) {
1542 * Report a query error. Log the error, and if neither the object ignore
1543 * flag nor the $ignoreErrors flag is set, throw a DBQueryError.
1545 * @param string $error
1547 * @param string $sql
1548 * @param string $fname
1549 * @param bool $ignoreErrors
1550 * @throws DBQueryError
1552 public function reportQueryError( $error, $errno, $sql, $fname, $ignoreErrors = false ) {
1553 if ( $ignoreErrors ) {
1554 $this->queryLogger
->debug( "SQL ERROR (ignored): $error\n" );
1556 $exception = $this->getQueryExceptionAndLog( $error, $errno, $sql, $fname );
1563 * @param string $error
1564 * @param string|int $errno
1565 * @param string $sql
1566 * @param string $fname
1569 private function getQueryExceptionAndLog( $error, $errno, $sql, $fname ) {
1570 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1571 $this->queryLogger
->error(
1572 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1573 $this->getLogContext( [
1574 'method' => __METHOD__
,
1577 'sql1line' => $sql1line,
1579 'trace' => ( new RuntimeException() )->getTraceAsString()
1582 $this->queryLogger
->debug( "SQL ERROR: " . $error . "\n" );
1583 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1584 if ( $wasQueryTimeout ) {
1585 $e = new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1587 $e = new DBQueryError( $this, $error, $errno, $sql, $fname );
1593 public function freeResult( $res ) {
1596 public function selectField(
1597 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1599 if ( $var === '*' ) { // sanity
1600 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1603 if ( !is_array( $options ) ) {
1604 $options = [ $options ];
1607 $options['LIMIT'] = 1;
1609 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1610 if ( $res === false ||
!$this->numRows( $res ) ) {
1614 $row = $this->fetchRow( $res );
1616 if ( $row !== false ) {
1617 return reset( $row );
1623 public function selectFieldValues(
1624 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1626 if ( $var === '*' ) { // sanity
1627 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1628 } elseif ( !is_string( $var ) ) { // sanity
1629 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1632 if ( !is_array( $options ) ) {
1633 $options = [ $options ];
1636 $res = $this->select( $table, [ 'value' => $var ], $cond, $fname, $options, $join_conds );
1637 if ( $res === false ) {
1642 foreach ( $res as $row ) {
1643 $values[] = $row->value
;
1650 * Returns an optional USE INDEX clause to go after the table, and a
1651 * string to go at the end of the query.
1653 * @param array $options Associative array of options to be turned into
1654 * an SQL query, valid keys are listed in the function.
1656 * @see Database::select()
1658 protected function makeSelectOptions( $options ) {
1659 $preLimitTail = $postLimitTail = '';
1664 foreach ( $options as $key => $option ) {
1665 if ( is_numeric( $key ) ) {
1666 $noKeyOptions[$option] = true;
1670 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1672 $preLimitTail .= $this->makeOrderBy( $options );
1674 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1675 $postLimitTail .= ' FOR UPDATE';
1678 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1679 $postLimitTail .= ' LOCK IN SHARE MODE';
1682 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1683 $startOpts .= 'DISTINCT';
1686 # Various MySQL extensions
1687 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1688 $startOpts .= ' /*! STRAIGHT_JOIN */';
1691 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1692 $startOpts .= ' HIGH_PRIORITY';
1695 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1696 $startOpts .= ' SQL_BIG_RESULT';
1699 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1700 $startOpts .= ' SQL_BUFFER_RESULT';
1703 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1704 $startOpts .= ' SQL_SMALL_RESULT';
1707 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1708 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1711 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1712 $startOpts .= ' SQL_CACHE';
1715 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1716 $startOpts .= ' SQL_NO_CACHE';
1719 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1720 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1724 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1725 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1730 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1734 * Returns an optional GROUP BY with an optional HAVING
1736 * @param array $options Associative array of options
1738 * @see Database::select()
1741 protected function makeGroupByWithHaving( $options ) {
1743 if ( isset( $options['GROUP BY'] ) ) {
1744 $gb = is_array( $options['GROUP BY'] )
1745 ?
implode( ',', $options['GROUP BY'] )
1746 : $options['GROUP BY'];
1747 $sql .= ' GROUP BY ' . $gb;
1749 if ( isset( $options['HAVING'] ) ) {
1750 $having = is_array( $options['HAVING'] )
1751 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1752 : $options['HAVING'];
1753 $sql .= ' HAVING ' . $having;
1760 * Returns an optional ORDER BY
1762 * @param array $options Associative array of options
1764 * @see Database::select()
1767 protected function makeOrderBy( $options ) {
1768 if ( isset( $options['ORDER BY'] ) ) {
1769 $ob = is_array( $options['ORDER BY'] )
1770 ?
implode( ',', $options['ORDER BY'] )
1771 : $options['ORDER BY'];
1773 return ' ORDER BY ' . $ob;
1779 public function select(
1780 $table, $vars, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1782 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1784 return $this->query( $sql, $fname );
1787 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1788 $options = [], $join_conds = []
1790 if ( is_array( $vars ) ) {
1791 $fields = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1796 $options = (array)$options;
1797 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1798 ?
$options['USE INDEX']
1801 isset( $options['IGNORE INDEX'] ) &&
1802 is_array( $options['IGNORE INDEX'] )
1804 ?
$options['IGNORE INDEX']
1808 $this->selectOptionsIncludeLocking( $options ) &&
1809 $this->selectFieldsOrOptionsAggregate( $vars, $options )
1811 // Some DB types (postgres/oracle) disallow FOR UPDATE with aggregate
1812 // functions. Discourage use of such queries to encourage compatibility.
1814 $this->deprecationLogger
,
1815 __METHOD__
. ": aggregation used with a locking SELECT ($fname)."
1819 if ( is_array( $table ) ) {
1821 $this->tableNamesWithIndexClauseOrJOIN(
1822 $table, $useIndexes, $ignoreIndexes, $join_conds );
1823 } elseif ( $table != '' ) {
1825 $this->tableNamesWithIndexClauseOrJOIN(
1826 [ $table ], $useIndexes, $ignoreIndexes, [] );
1831 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1832 $this->makeSelectOptions( $options );
1834 if ( is_array( $conds ) ) {
1835 $conds = $this->makeList( $conds, self
::LIST_AND
);
1838 if ( $conds === null ||
$conds === false ) {
1839 $this->queryLogger
->warning(
1843 . ' with incorrect parameters: $conds must be a string or an array'
1848 if ( $conds === '' ||
$conds === '*' ) {
1849 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex $preLimitTail";
1850 } elseif ( is_string( $conds ) ) {
1851 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex " .
1852 "WHERE $conds $preLimitTail";
1854 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1857 if ( isset( $options['LIMIT'] ) ) {
1858 $sql = $this->limitResult( $sql, $options['LIMIT'],
1859 $options['OFFSET'] ??
false );
1861 $sql = "$sql $postLimitTail";
1863 if ( isset( $options['EXPLAIN'] ) ) {
1864 $sql = 'EXPLAIN ' . $sql;
1870 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1871 $options = [], $join_conds = []
1873 $options = (array)$options;
1874 $options['LIMIT'] = 1;
1875 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1877 if ( $res === false ) {
1881 if ( !$this->numRows( $res ) ) {
1885 $obj = $this->fetchObject( $res );
1890 public function estimateRowCount(
1891 $table, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1893 $conds = $this->normalizeConditions( $conds, $fname );
1894 $column = $this->extractSingleFieldFromList( $var );
1895 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1896 $conds[] = "$column IS NOT NULL";
1899 $res = $this->select(
1900 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1902 $row = $res ?
$this->fetchRow( $res ) : [];
1904 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1907 public function selectRowCount(
1908 $tables, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1910 $conds = $this->normalizeConditions( $conds, $fname );
1911 $column = $this->extractSingleFieldFromList( $var );
1912 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1913 $conds[] = "$column IS NOT NULL";
1916 $res = $this->select(
1918 'tmp_count' => $this->buildSelectSubquery(
1927 [ 'rowcount' => 'COUNT(*)' ],
1931 $row = $res ?
$this->fetchRow( $res ) : [];
1933 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1937 * @param string|array $options
1940 private function selectOptionsIncludeLocking( $options ) {
1941 $options = (array)$options;
1942 foreach ( [ 'FOR UPDATE', 'LOCK IN SHARE MODE' ] as $lock ) {
1943 if ( in_array( $lock, $options, true ) ) {
1952 * @param array|string $fields
1953 * @param array|string $options
1956 private function selectFieldsOrOptionsAggregate( $fields, $options ) {
1957 foreach ( (array)$options as $key => $value ) {
1958 if ( is_string( $key ) ) {
1959 if ( preg_match( '/^(?:GROUP BY|HAVING)$/i', $key ) ) {
1962 } elseif ( is_string( $value ) ) {
1963 if ( preg_match( '/^(?:DISTINCT|DISTINCTROW)$/i', $value ) ) {
1969 $regex = '/^(?:COUNT|MIN|MAX|SUM|GROUP_CONCAT|LISTAGG|ARRAY_AGG)\s*\\(/i';
1970 foreach ( (array)$fields as $field ) {
1971 if ( is_string( $field ) && preg_match( $regex, $field ) ) {
1980 * @param array|string $conds
1981 * @param string $fname
1984 final protected function normalizeConditions( $conds, $fname ) {
1985 if ( $conds === null ||
$conds === false ) {
1986 $this->queryLogger
->warning(
1990 . ' with incorrect parameters: $conds must be a string or an array'
1995 if ( !is_array( $conds ) ) {
1996 $conds = ( $conds === '' ) ?
[] : [ $conds ];
2003 * @param array|string $var Field parameter in the style of select()
2004 * @return string|null Column name or null; ignores aliases
2005 * @throws DBUnexpectedError Errors out if multiple columns are given
2007 final protected function extractSingleFieldFromList( $var ) {
2008 if ( is_array( $var ) ) {
2011 } elseif ( count( $var ) == 1 ) {
2012 $column = $var[0] ??
reset( $var );
2014 throw new DBUnexpectedError( $this, __METHOD__
. ': got multiple columns.' );
2023 public function lockForUpdate(
2024 $table, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
2026 if ( !$this->trxLevel
&& !$this->getFlag( self
::DBO_TRX
) ) {
2027 throw new DBUnexpectedError(
2029 __METHOD__
. ': no transaction is active nor is DBO_TRX set'
2033 $options = (array)$options;
2034 $options[] = 'FOR UPDATE';
2036 return $this->selectRowCount( $table, '*', $conds, $fname, $options, $join_conds );
2040 * Removes most variables from an SQL query and replaces them with X or N for numbers.
2041 * It's only slightly flawed. Don't use for anything important.
2043 * @param string $sql A SQL Query
2047 protected static function generalizeSQL( $sql ) {
2048 # This does the same as the regexp below would do, but in such a way
2049 # as to avoid crashing php on some large strings.
2050 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
2052 $sql = str_replace( "\\\\", '', $sql );
2053 $sql = str_replace( "\\'", '', $sql );
2054 $sql = str_replace( "\\\"", '', $sql );
2055 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
2056 $sql = preg_replace( '/".*"/s', "'X'", $sql );
2058 # All newlines, tabs, etc replaced by single space
2059 $sql = preg_replace( '/\s+/', ' ', $sql );
2062 # except the ones surrounded by characters, e.g. l10n
2063 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
2064 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
2069 public function fieldExists( $table, $field, $fname = __METHOD__
) {
2070 $info = $this->fieldInfo( $table, $field );
2075 public function indexExists( $table, $index, $fname = __METHOD__
) {
2076 if ( !$this->tableExists( $table ) ) {
2080 $info = $this->indexInfo( $table, $index, $fname );
2081 if ( is_null( $info ) ) {
2084 return $info !== false;
2088 abstract public function tableExists( $table, $fname = __METHOD__
);
2090 public function indexUnique( $table, $index ) {
2091 $indexInfo = $this->indexInfo( $table, $index );
2093 if ( !$indexInfo ) {
2097 return !$indexInfo[0]->Non_unique
;
2101 * Helper for Database::insert().
2103 * @param array $options
2106 protected function makeInsertOptions( $options ) {
2107 return implode( ' ', $options );
2110 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
2111 # No rows to insert, easy just return now
2112 if ( !count( $a ) ) {
2116 $table = $this->tableName( $table );
2118 if ( !is_array( $options ) ) {
2119 $options = [ $options ];
2122 $options = $this->makeInsertOptions( $options );
2124 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
2126 $keys = array_keys( $a[0] );
2129 $keys = array_keys( $a );
2132 $sql = 'INSERT ' . $options .
2133 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
2137 foreach ( $a as $row ) {
2143 $sql .= '(' . $this->makeList( $row ) . ')';
2146 $sql .= '(' . $this->makeList( $a ) . ')';
2149 $this->query( $sql, $fname );
2155 * Make UPDATE options array for Database::makeUpdateOptions
2157 * @param array $options
2160 protected function makeUpdateOptionsArray( $options ) {
2161 if ( !is_array( $options ) ) {
2162 $options = [ $options ];
2167 if ( in_array( 'IGNORE', $options ) ) {
2175 * Make UPDATE options for the Database::update function
2177 * @param array $options The options passed to Database::update
2180 protected function makeUpdateOptions( $options ) {
2181 $opts = $this->makeUpdateOptionsArray( $options );
2183 return implode( ' ', $opts );
2186 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
2187 $table = $this->tableName( $table );
2188 $opts = $this->makeUpdateOptions( $options );
2189 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
2191 if ( $conds !== [] && $conds !== '*' ) {
2192 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
2195 $this->query( $sql, $fname );
2200 public function makeList( $a, $mode = self
::LIST_COMMA
) {
2201 if ( !is_array( $a ) ) {
2202 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
2208 foreach ( $a as $field => $value ) {
2210 if ( $mode == self
::LIST_AND
) {
2212 } elseif ( $mode == self
::LIST_OR
) {
2221 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
2222 $list .= "($value)";
2223 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
2226 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
2228 // Remove null from array to be handled separately if found
2229 $includeNull = false;
2230 foreach ( array_keys( $value, null, true ) as $nullKey ) {
2231 $includeNull = true;
2232 unset( $value[$nullKey] );
2234 if ( count( $value ) == 0 && !$includeNull ) {
2235 throw new InvalidArgumentException(
2236 __METHOD__
. ": empty input for field $field" );
2237 } elseif ( count( $value ) == 0 ) {
2238 // only check if $field is null
2239 $list .= "$field IS NULL";
2241 // IN clause contains at least one valid element
2242 if ( $includeNull ) {
2243 // Group subconditions to ensure correct precedence
2246 if ( count( $value ) == 1 ) {
2247 // Special-case single values, as IN isn't terribly efficient
2248 // Don't necessarily assume the single key is 0; we don't
2249 // enforce linear numeric ordering on other arrays here.
2250 $value = array_values( $value )[0];
2251 $list .= $field . " = " . $this->addQuotes( $value );
2253 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
2255 // if null present in array, append IS NULL
2256 if ( $includeNull ) {
2257 $list .= " OR $field IS NULL)";
2260 } elseif ( $value === null ) {
2261 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
2262 $list .= "$field IS ";
2263 } elseif ( $mode == self
::LIST_SET
) {
2264 $list .= "$field = ";
2269 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
2271 $list .= "$field = ";
2273 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
2280 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
2283 foreach ( $data as $base => $sub ) {
2284 if ( count( $sub ) ) {
2285 $conds[] = $this->makeList(
2286 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
2292 return $this->makeList( $conds, self
::LIST_OR
);
2294 // Nothing to search for...
2299 public function aggregateValue( $valuedata, $valuename = 'value' ) {
2303 public function bitNot( $field ) {
2307 public function bitAnd( $fieldLeft, $fieldRight ) {
2308 return "($fieldLeft & $fieldRight)";
2311 public function bitOr( $fieldLeft, $fieldRight ) {
2312 return "($fieldLeft | $fieldRight)";
2315 public function buildConcat( $stringList ) {
2316 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2319 public function buildGroupConcatField(
2320 $delim, $table, $field, $conds = '', $join_conds = []
2322 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
2324 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2327 public function buildSubstring( $input, $startPosition, $length = null ) {
2328 $this->assertBuildSubstringParams( $startPosition, $length );
2329 $functionBody = "$input FROM $startPosition";
2330 if ( $length !== null ) {
2331 $functionBody .= " FOR $length";
2333 return 'SUBSTRING(' . $functionBody . ')';
2337 * Check type and bounds for parameters to self::buildSubstring()
2339 * All supported databases have substring functions that behave the same for
2340 * positive $startPosition and non-negative $length, but behaviors differ when
2341 * given 0 or negative $startPosition or negative $length. The simplest
2342 * solution to that is to just forbid those values.
2344 * @param int $startPosition
2345 * @param int|null $length
2348 protected function assertBuildSubstringParams( $startPosition, $length ) {
2349 if ( !is_int( $startPosition ) ||
$startPosition <= 0 ) {
2350 throw new InvalidArgumentException(
2351 '$startPosition must be a positive integer'
2354 if ( !( is_int( $length ) && $length >= 0 ||
$length === null ) ) {
2355 throw new InvalidArgumentException(
2356 '$length must be null or an integer greater than or equal to 0'
2361 public function buildStringCast( $field ) {
2362 // In theory this should work for any standards-compliant
2363 // SQL implementation, although it may not be the best way to do it.
2364 return "CAST( $field AS CHARACTER )";
2367 public function buildIntegerCast( $field ) {
2368 return 'CAST( ' . $field . ' AS INTEGER )';
2371 public function buildSelectSubquery(
2372 $table, $vars, $conds = '', $fname = __METHOD__
,
2373 $options = [], $join_conds = []
2375 return new Subquery(
2376 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2380 public function databasesAreIndependent() {
2384 final public function selectDB( $db ) {
2385 $this->selectDomain( new DatabaseDomain(
2387 $this->currentDomain
->getSchema(),
2388 $this->currentDomain
->getTablePrefix()
2394 final public function selectDomain( $domain ) {
2395 $this->doSelectDomain( DatabaseDomain
::newFromId( $domain ) );
2398 protected function doSelectDomain( DatabaseDomain
$domain ) {
2399 $this->currentDomain
= $domain;
2402 public function getDBname() {
2403 return $this->currentDomain
->getDatabase();
2406 public function getServer() {
2407 return $this->server
;
2410 public function tableName( $name, $format = 'quoted' ) {
2411 if ( $name instanceof Subquery
) {
2412 throw new DBUnexpectedError(
2414 __METHOD__
. ': got Subquery instance when expecting a string.'
2418 # Skip the entire process when we have a string quoted on both ends.
2419 # Note that we check the end so that we will still quote any use of
2420 # use of `database`.table. But won't break things if someone wants
2421 # to query a database table with a dot in the name.
2422 if ( $this->isQuotedIdentifier( $name ) ) {
2426 # Lets test for any bits of text that should never show up in a table
2427 # name. Basically anything like JOIN or ON which are actually part of
2428 # SQL queries, but may end up inside of the table value to combine
2429 # sql. Such as how the API is doing.
2430 # Note that we use a whitespace test rather than a \b test to avoid
2431 # any remote case where a word like on may be inside of a table name
2432 # surrounded by symbols which may be considered word breaks.
2433 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2434 $this->queryLogger
->warning(
2435 __METHOD__
. ": use of subqueries is not supported this way.",
2436 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2442 # Split database and table into proper variables.
2443 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2445 # Quote $table and apply the prefix if not quoted.
2446 # $tableName might be empty if this is called from Database::replaceVars()
2447 $tableName = "{$prefix}{$table}";
2448 if ( $format === 'quoted'
2449 && !$this->isQuotedIdentifier( $tableName )
2450 && $tableName !== ''
2452 $tableName = $this->addIdentifierQuotes( $tableName );
2455 # Quote $schema and $database and merge them with the table name if needed
2456 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2457 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2463 * Get the table components needed for a query given the currently selected database
2465 * @param string $name Table name in the form of db.schema.table, db.table, or table
2466 * @return array (DB name or "" for default, schema name, table prefix, table name)
2468 protected function qualifiedTableComponents( $name ) {
2469 # We reverse the explode so that database.table and table both output the correct table.
2470 $dbDetails = explode( '.', $name, 3 );
2471 if ( count( $dbDetails ) == 3 ) {
2472 list( $database, $schema, $table ) = $dbDetails;
2473 # We don't want any prefix added in this case
2475 } elseif ( count( $dbDetails ) == 2 ) {
2476 list( $database, $table ) = $dbDetails;
2477 # We don't want any prefix added in this case
2479 # In dbs that support it, $database may actually be the schema
2480 # but that doesn't affect any of the functionality here
2483 list( $table ) = $dbDetails;
2484 if ( isset( $this->tableAliases
[$table] ) ) {
2485 $database = $this->tableAliases
[$table]['dbname'];
2486 $schema = is_string( $this->tableAliases
[$table]['schema'] )
2487 ?
$this->tableAliases
[$table]['schema']
2488 : $this->relationSchemaQualifier();
2489 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
2490 ?
$this->tableAliases
[$table]['prefix']
2491 : $this->tablePrefix();
2494 $schema = $this->relationSchemaQualifier(); # Default schema
2495 $prefix = $this->tablePrefix(); # Default prefix
2499 return [ $database, $schema, $prefix, $table ];
2503 * @param string|null $namespace Database or schema
2504 * @param string $relation Name of table, view, sequence, etc...
2505 * @param string $format One of (raw, quoted)
2506 * @return string Relation name with quoted and merged $namespace as needed
2508 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2509 if ( strlen( $namespace ) ) {
2510 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2511 $namespace = $this->addIdentifierQuotes( $namespace );
2513 $relation = $namespace . '.' . $relation;
2519 public function tableNames() {
2520 $inArray = func_get_args();
2523 foreach ( $inArray as $name ) {
2524 $retVal[$name] = $this->tableName( $name );
2530 public function tableNamesN() {
2531 $inArray = func_get_args();
2534 foreach ( $inArray as $name ) {
2535 $retVal[] = $this->tableName( $name );
2542 * Get an aliased table name
2544 * This returns strings like "tableName AS newTableName" for aliased tables
2545 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2547 * @see Database::tableName()
2548 * @param string|Subquery $table Table name or object with a 'sql' field
2549 * @param string|bool $alias Table alias (optional)
2550 * @return string SQL name for aliased table. Will not alias a table to its own name
2552 protected function tableNameWithAlias( $table, $alias = false ) {
2553 if ( is_string( $table ) ) {
2554 $quotedTable = $this->tableName( $table );
2555 } elseif ( $table instanceof Subquery
) {
2556 $quotedTable = (string)$table;
2558 throw new InvalidArgumentException( "Table must be a string or Subquery." );
2561 if ( $alias === false ||
$alias === $table ) {
2562 if ( $table instanceof Subquery
) {
2563 throw new InvalidArgumentException( "Subquery table missing alias." );
2566 return $quotedTable;
2568 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2573 * Gets an array of aliased table names
2575 * @param array $tables [ [alias] => table ]
2576 * @return string[] See tableNameWithAlias()
2578 protected function tableNamesWithAlias( $tables ) {
2580 foreach ( $tables as $alias => $table ) {
2581 if ( is_numeric( $alias ) ) {
2584 $retval[] = $this->tableNameWithAlias( $table, $alias );
2591 * Get an aliased field name
2592 * e.g. fieldName AS newFieldName
2594 * @param string $name Field name
2595 * @param string|bool $alias Alias (optional)
2596 * @return string SQL name for aliased field. Will not alias a field to its own name
2598 protected function fieldNameWithAlias( $name, $alias = false ) {
2599 if ( !$alias ||
(string)$alias === (string)$name ) {
2602 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2607 * Gets an array of aliased field names
2609 * @param array $fields [ [alias] => field ]
2610 * @return string[] See fieldNameWithAlias()
2612 protected function fieldNamesWithAlias( $fields ) {
2614 foreach ( $fields as $alias => $field ) {
2615 if ( is_numeric( $alias ) ) {
2618 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2625 * Get the aliased table name clause for a FROM clause
2626 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2628 * @param array $tables ( [alias] => table )
2629 * @param array $use_index Same as for select()
2630 * @param array $ignore_index Same as for select()
2631 * @param array $join_conds Same as for select()
2634 protected function tableNamesWithIndexClauseOrJOIN(
2635 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2639 $use_index = (array)$use_index;
2640 $ignore_index = (array)$ignore_index;
2641 $join_conds = (array)$join_conds;
2643 foreach ( $tables as $alias => $table ) {
2644 if ( !is_string( $alias ) ) {
2645 // No alias? Set it equal to the table name
2649 if ( is_array( $table ) ) {
2650 // A parenthesized group
2651 if ( count( $table ) > 1 ) {
2652 $joinedTable = '(' .
2653 $this->tableNamesWithIndexClauseOrJOIN(
2654 $table, $use_index, $ignore_index, $join_conds ) . ')';
2657 $innerTable = reset( $table );
2658 $innerAlias = key( $table );
2659 $joinedTable = $this->tableNameWithAlias(
2661 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2665 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2668 // Is there a JOIN clause for this table?
2669 if ( isset( $join_conds[$alias] ) ) {
2670 list( $joinType, $conds ) = $join_conds[$alias];
2671 $tableClause = $joinType;
2672 $tableClause .= ' ' . $joinedTable;
2673 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2674 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2676 $tableClause .= ' ' . $use;
2679 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2680 $ignore = $this->ignoreIndexClause(
2681 implode( ',', (array)$ignore_index[$alias] ) );
2682 if ( $ignore != '' ) {
2683 $tableClause .= ' ' . $ignore;
2686 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2688 $tableClause .= ' ON (' . $on . ')';
2691 $retJOIN[] = $tableClause;
2692 } elseif ( isset( $use_index[$alias] ) ) {
2693 // Is there an INDEX clause for this table?
2694 $tableClause = $joinedTable;
2695 $tableClause .= ' ' . $this->useIndexClause(
2696 implode( ',', (array)$use_index[$alias] )
2699 $ret[] = $tableClause;
2700 } elseif ( isset( $ignore_index[$alias] ) ) {
2701 // Is there an INDEX clause for this table?
2702 $tableClause = $joinedTable;
2703 $tableClause .= ' ' . $this->ignoreIndexClause(
2704 implode( ',', (array)$ignore_index[$alias] )
2707 $ret[] = $tableClause;
2709 $tableClause = $joinedTable;
2711 $ret[] = $tableClause;
2715 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2716 $implicitJoins = $ret ?
implode( ',', $ret ) : "";
2717 $explicitJoins = $retJOIN ?
implode( ' ', $retJOIN ) : "";
2719 // Compile our final table clause
2720 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2724 * Allows for index remapping in queries where this is not consistent across DBMS
2726 * @param string $index
2729 protected function indexName( $index ) {
2730 return $this->indexAliases
[$index] ??
$index;
2733 public function addQuotes( $s ) {
2734 if ( $s instanceof Blob
) {
2737 if ( $s === null ) {
2739 } elseif ( is_bool( $s ) ) {
2742 # This will also quote numeric values. This should be harmless,
2743 # and protects against weird problems that occur when they really
2744 # _are_ strings such as article titles and string->number->string
2745 # conversion is not 1:1.
2746 return "'" . $this->strencode( $s ) . "'";
2750 public function addIdentifierQuotes( $s ) {
2751 return '"' . str_replace( '"', '""', $s ) . '"';
2755 * Returns if the given identifier looks quoted or not according to
2756 * the database convention for quoting identifiers .
2758 * @note Do not use this to determine if untrusted input is safe.
2759 * A malicious user can trick this function.
2760 * @param string $name
2763 public function isQuotedIdentifier( $name ) {
2764 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2769 * @param string $escapeChar
2772 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2773 return str_replace( [ $escapeChar, '%', '_' ],
2774 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2778 public function buildLike() {
2779 $params = func_get_args();
2781 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2782 $params = $params[0];
2787 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2788 // may escape backslashes, creating problems of double escaping. The `
2789 // character has good cross-DBMS compatibility, avoiding special operators
2790 // in MS SQL like ^ and %
2793 foreach ( $params as $value ) {
2794 if ( $value instanceof LikeMatch
) {
2795 $s .= $value->toString();
2797 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2802 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2805 public function anyChar() {
2806 return new LikeMatch( '_' );
2809 public function anyString() {
2810 return new LikeMatch( '%' );
2813 public function nextSequenceValue( $seqName ) {
2818 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2819 * is only needed because a) MySQL must be as efficient as possible due to
2820 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2821 * which index to pick. Anyway, other databases might have different
2822 * indexes on a given table. So don't bother overriding this unless you're
2824 * @param string $index
2827 public function useIndexClause( $index ) {
2832 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2833 * is only needed because a) MySQL must be as efficient as possible due to
2834 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2835 * which index to pick. Anyway, other databases might have different
2836 * indexes on a given table. So don't bother overriding this unless you're
2838 * @param string $index
2841 public function ignoreIndexClause( $index ) {
2845 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2846 if ( count( $rows ) == 0 ) {
2850 $uniqueIndexes = (array)$uniqueIndexes;
2852 if ( !is_array( reset( $rows ) ) ) {
2857 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2858 $affectedRowCount = 0;
2859 foreach ( $rows as $row ) {
2860 // Delete rows which collide with this one
2861 $indexWhereClauses = [];
2862 foreach ( $uniqueIndexes as $index ) {
2863 $indexColumns = (array)$index;
2864 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2865 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2866 throw new DBUnexpectedError(
2868 'New record does not provide all values for unique key (' .
2869 implode( ', ', $indexColumns ) . ')'
2871 } elseif ( in_array( null, $indexRowValues, true ) ) {
2872 throw new DBUnexpectedError(
2874 'New record has a null value for unique key (' .
2875 implode( ', ', $indexColumns ) . ')'
2878 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND
);
2881 if ( $indexWhereClauses ) {
2882 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR
), $fname );
2883 $affectedRowCount +
= $this->affectedRows();
2886 // Now insert the row
2887 $this->insert( $table, $row, $fname );
2888 $affectedRowCount +
= $this->affectedRows();
2890 $this->endAtomic( $fname );
2891 $this->affectedRowCount
= $affectedRowCount;
2892 } catch ( Exception
$e ) {
2893 $this->cancelAtomic( $fname );
2899 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2902 * @param string $table Table name
2903 * @param array|string $rows Row(s) to insert
2904 * @param string $fname Caller function name
2906 protected function nativeReplace( $table, $rows, $fname ) {
2907 $table = $this->tableName( $table );
2910 if ( !is_array( reset( $rows ) ) ) {
2914 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2917 foreach ( $rows as $row ) {
2924 $sql .= '(' . $this->makeList( $row ) . ')';
2927 $this->query( $sql, $fname );
2930 public function upsert( $table, array $rows, $uniqueIndexes, array $set,
2933 if ( $rows === [] ) {
2934 return true; // nothing to do
2937 $uniqueIndexes = (array)$uniqueIndexes;
2938 if ( !is_array( reset( $rows ) ) ) {
2942 if ( count( $uniqueIndexes ) ) {
2943 $clauses = []; // list WHERE clauses that each identify a single row
2944 foreach ( $rows as $row ) {
2945 foreach ( $uniqueIndexes as $index ) {
2946 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2947 $rowKey = []; // unique key to this row
2948 foreach ( $index as $column ) {
2949 $rowKey[$column] = $row[$column];
2951 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2954 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2959 $affectedRowCount = 0;
2961 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2962 # Update any existing conflicting row(s)
2963 if ( $where !== false ) {
2964 $this->update( $table, $set, $where, $fname );
2965 $affectedRowCount +
= $this->affectedRows();
2967 # Now insert any non-conflicting row(s)
2968 $this->insert( $table, $rows, $fname, [ 'IGNORE' ] );
2969 $affectedRowCount +
= $this->affectedRows();
2970 $this->endAtomic( $fname );
2971 $this->affectedRowCount
= $affectedRowCount;
2972 } catch ( Exception
$e ) {
2973 $this->cancelAtomic( $fname );
2980 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2984 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2987 $delTable = $this->tableName( $delTable );
2988 $joinTable = $this->tableName( $joinTable );
2989 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2990 if ( $conds != '*' ) {
2991 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2995 $this->query( $sql, $fname );
2998 public function textFieldSize( $table, $field ) {
2999 $table = $this->tableName( $table );
3000 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
3001 $res = $this->query( $sql, __METHOD__
);
3002 $row = $this->fetchObject( $res );
3006 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
3015 public function delete( $table, $conds, $fname = __METHOD__
) {
3017 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
3020 $table = $this->tableName( $table );
3021 $sql = "DELETE FROM $table";
3023 if ( $conds != '*' ) {
3024 if ( is_array( $conds ) ) {
3025 $conds = $this->makeList( $conds, self
::LIST_AND
);
3027 $sql .= ' WHERE ' . $conds;
3030 $this->query( $sql, $fname );
3035 final public function insertSelect(
3036 $destTable, $srcTable, $varMap, $conds,
3037 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3039 static $hints = [ 'NO_AUTO_COLUMNS' ];
3041 $insertOptions = (array)$insertOptions;
3042 $selectOptions = (array)$selectOptions;
3044 if ( $this->cliMode
&& $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
3045 // For massive migrations with downtime, we don't want to select everything
3046 // into memory and OOM, so do all this native on the server side if possible.
3047 $this->nativeInsertSelect(
3053 array_diff( $insertOptions, $hints ),
3058 $this->nonNativeInsertSelect(
3064 array_diff( $insertOptions, $hints ),
3074 * @param array $insertOptions INSERT options
3075 * @param array $selectOptions SELECT options
3076 * @return bool Whether an INSERT SELECT with these options will be replication safe
3079 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
3084 * Implementation of insertSelect() based on select() and insert()
3086 * @see IDatabase::insertSelect()
3088 * @param string $destTable
3089 * @param string|array $srcTable
3090 * @param array $varMap
3091 * @param array $conds
3092 * @param string $fname
3093 * @param array $insertOptions
3094 * @param array $selectOptions
3095 * @param array $selectJoinConds
3097 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3098 $fname = __METHOD__
,
3099 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3101 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
3102 // on only the master (without needing row-based-replication). It also makes it easy to
3103 // know how big the INSERT is going to be.
3105 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
3106 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
3108 $selectOptions[] = 'FOR UPDATE';
3109 $res = $this->select(
3110 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
3117 $affectedRowCount = 0;
3118 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
3121 foreach ( $res as $row ) {
3122 $rows[] = (array)$row;
3124 // Avoid inserts that are too huge
3125 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize
) {
3126 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3130 $affectedRowCount +
= $this->affectedRows();
3134 if ( $rows && $ok ) {
3135 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3137 $affectedRowCount +
= $this->affectedRows();
3141 $this->endAtomic( $fname );
3142 $this->affectedRowCount
= $affectedRowCount;
3144 $this->cancelAtomic( $fname );
3146 } catch ( Exception
$e ) {
3147 $this->cancelAtomic( $fname );
3153 * Native server-side implementation of insertSelect() for situations where
3154 * we don't want to select everything into memory
3156 * @see IDatabase::insertSelect()
3157 * @param string $destTable
3158 * @param string|array $srcTable
3159 * @param array $varMap
3160 * @param array $conds
3161 * @param string $fname
3162 * @param array $insertOptions
3163 * @param array $selectOptions
3164 * @param array $selectJoinConds
3166 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3167 $fname = __METHOD__
,
3168 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3170 $destTable = $this->tableName( $destTable );
3172 if ( !is_array( $insertOptions ) ) {
3173 $insertOptions = [ $insertOptions ];
3176 $insertOptions = $this->makeInsertOptions( $insertOptions );
3178 $selectSql = $this->selectSQLText(
3180 array_values( $varMap ),
3187 $sql = "INSERT $insertOptions" .
3188 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
3191 $this->query( $sql, $fname );
3195 * Construct a LIMIT query with optional offset. This is used for query
3196 * pages. The SQL should be adjusted so that only the first $limit rows
3197 * are returned. If $offset is provided as well, then the first $offset
3198 * rows should be discarded, and the next $limit rows should be returned.
3199 * If the result of the query is not ordered, then the rows to be returned
3200 * are theoretically arbitrary.
3202 * $sql is expected to be a SELECT, if that makes a difference.
3204 * The version provided by default works in MySQL and SQLite. It will very
3205 * likely need to be overridden for most other DBMSes.
3207 * @param string $sql SQL query we will append the limit too
3208 * @param int $limit The SQL limit
3209 * @param int|bool $offset The SQL offset (default false)
3210 * @throws DBUnexpectedError
3213 public function limitResult( $sql, $limit, $offset = false ) {
3214 if ( !is_numeric( $limit ) ) {
3215 throw new DBUnexpectedError( $this,
3216 "Invalid non-numeric limit passed to limitResult()\n" );
3219 return "$sql LIMIT "
3220 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
3224 public function unionSupportsOrderAndLimit() {
3225 return true; // True for almost every DB supported
3228 public function unionQueries( $sqls, $all ) {
3229 $glue = $all ?
') UNION ALL (' : ') UNION (';
3231 return '(' . implode( $glue, $sqls ) . ')';
3234 public function unionConditionPermutations(
3235 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
3236 $options = [], $join_conds = []
3238 // First, build the Cartesian product of $permute_conds
3240 foreach ( $permute_conds as $field => $values ) {
3242 // Skip empty $values
3245 $values = array_unique( $values ); // For sanity
3247 foreach ( $conds as $cond ) {
3248 foreach ( $values as $value ) {
3249 $cond[$field] = $value;
3250 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
3256 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
3258 // If there's just one condition and no subordering, hand off to
3259 // selectSQLText directly.
3260 if ( count( $conds ) === 1 &&
3261 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
3263 return $this->selectSQLText(
3264 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
3268 // Otherwise, we need to pull out the order and limit to apply after
3269 // the union. Then build the SQL queries for each set of conditions in
3270 // $conds. Then union them together (using UNION ALL, because the
3271 // product *should* already be distinct).
3272 $orderBy = $this->makeOrderBy( $options );
3273 $limit = $options['LIMIT'] ??
null;
3274 $offset = $options['OFFSET'] ??
false;
3275 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
3276 if ( !$this->unionSupportsOrderAndLimit() ) {
3277 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
3279 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
3280 $options['ORDER BY'] = $options['INNER ORDER BY'];
3282 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
3283 // We need to increase the limit by the offset rather than
3284 // using the offset directly, otherwise it'll skip incorrectly
3285 // in the subqueries.
3286 $options['LIMIT'] = $limit +
$offset;
3287 unset( $options['OFFSET'] );
3292 foreach ( $conds as $cond ) {
3293 $sqls[] = $this->selectSQLText(
3294 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
3297 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
3298 if ( $limit !== null ) {
3299 $sql = $this->limitResult( $sql, $limit, $offset );
3305 public function conditional( $cond, $trueVal, $falseVal ) {
3306 if ( is_array( $cond ) ) {
3307 $cond = $this->makeList( $cond, self
::LIST_AND
);
3310 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
3313 public function strreplace( $orig, $old, $new ) {
3314 return "REPLACE({$orig}, {$old}, {$new})";
3317 public function getServerUptime() {
3321 public function wasDeadlock() {
3325 public function wasLockTimeout() {
3329 public function wasConnectionLoss() {
3330 return $this->wasConnectionError( $this->lastErrno() );
3333 public function wasReadOnlyError() {
3337 public function wasErrorReissuable() {
3339 $this->wasDeadlock() ||
3340 $this->wasLockTimeout() ||
3341 $this->wasConnectionLoss()
3346 * Do not use this method outside of Database/DBError classes
3348 * @param int|string $errno
3349 * @return bool Whether the given query error was a connection drop
3351 public function wasConnectionError( $errno ) {
3356 * @return bool Whether it is known that the last query error only caused statement rollback
3357 * @note This is for backwards compatibility for callers catching DBError exceptions in
3358 * order to ignore problems like duplicate key errors or foriegn key violations
3361 protected function wasKnownStatementRollbackError() {
3362 return false; // don't know; it could have caused a transaction rollback
3365 public function deadlockLoop() {
3366 $args = func_get_args();
3367 $function = array_shift( $args );
3368 $tries = self
::DEADLOCK_TRIES
;
3370 $this->begin( __METHOD__
);
3373 /** @var Exception $e */
3377 $retVal = $function( ...$args );
3379 } catch ( DBQueryError
$e ) {
3380 if ( $this->wasDeadlock() ) {
3381 // Retry after a randomized delay
3382 usleep( mt_rand( self
::DEADLOCK_DELAY_MIN
, self
::DEADLOCK_DELAY_MAX
) );
3384 // Throw the error back up
3388 } while ( --$tries > 0 );
3390 if ( $tries <= 0 ) {
3391 // Too many deadlocks; give up
3392 $this->rollback( __METHOD__
);
3395 $this->commit( __METHOD__
);
3401 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
3402 # Real waits are implemented in the subclass.
3406 public function getReplicaPos() {
3411 public function getMasterPos() {
3416 public function serverIsReadOnly() {
3420 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
3421 if ( !$this->trxLevel
) {
3422 throw new DBUnexpectedError( $this, "No transaction is active." );
3424 $this->trxEndCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3427 final public function onTransactionCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3428 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3429 // Start an implicit transaction similar to how query() does
3430 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3431 $this->trxAutomatic
= true;
3434 $this->trxIdleCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3435 if ( !$this->trxLevel
) {
3436 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
3440 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
3441 $this->onTransactionCommitOrIdle( $callback, $fname );
3444 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3445 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3446 // Start an implicit transaction similar to how query() does
3447 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3448 $this->trxAutomatic
= true;
3451 if ( $this->trxLevel
) {
3452 $this->trxPreCommitCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3454 // No transaction is active nor will start implicitly, so make one for this callback
3455 $this->startAtomic( __METHOD__
, self
::ATOMIC_CANCELABLE
);
3458 $this->endAtomic( __METHOD__
);
3459 } catch ( Exception
$e ) {
3460 $this->cancelAtomic( __METHOD__
);
3467 * @return AtomicSectionIdentifier|null ID of the topmost atomic section level
3469 private function currentAtomicSectionId() {
3470 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3471 $levelInfo = end( $this->trxAtomicLevels
);
3473 return $levelInfo[1];
3480 * @param AtomicSectionIdentifier $old
3481 * @param AtomicSectionIdentifier $new
3483 private function reassignCallbacksForSection(
3484 AtomicSectionIdentifier
$old, AtomicSectionIdentifier
$new
3486 foreach ( $this->trxPreCommitCallbacks
as $key => $info ) {
3487 if ( $info[2] === $old ) {
3488 $this->trxPreCommitCallbacks
[$key][2] = $new;
3491 foreach ( $this->trxIdleCallbacks
as $key => $info ) {
3492 if ( $info[2] === $old ) {
3493 $this->trxIdleCallbacks
[$key][2] = $new;
3496 foreach ( $this->trxEndCallbacks
as $key => $info ) {
3497 if ( $info[2] === $old ) {
3498 $this->trxEndCallbacks
[$key][2] = $new;
3504 * @param AtomicSectionIdentifier[] $sectionIds ID of an actual savepoint
3505 * @throws UnexpectedValueException
3507 private function modifyCallbacksForCancel( array $sectionIds ) {
3508 // Cancel the "on commit" callbacks owned by this savepoint
3509 $this->trxIdleCallbacks
= array_filter(
3510 $this->trxIdleCallbacks
,
3511 function ( $entry ) use ( $sectionIds ) {
3512 return !in_array( $entry[2], $sectionIds, true );
3515 $this->trxPreCommitCallbacks
= array_filter(
3516 $this->trxPreCommitCallbacks
,
3517 function ( $entry ) use ( $sectionIds ) {
3518 return !in_array( $entry[2], $sectionIds, true );
3521 // Make "on resolution" callbacks owned by this savepoint to perceive a rollback
3522 foreach ( $this->trxEndCallbacks
as $key => $entry ) {
3523 if ( in_array( $entry[2], $sectionIds, true ) ) {
3524 $callback = $entry[0];
3525 $this->trxEndCallbacks
[$key][0] = function () use ( $callback ) {
3526 return $callback( self
::TRIGGER_ROLLBACK
, $this );
3532 final public function setTransactionListener( $name, callable
$callback = null ) {
3534 $this->trxRecurringCallbacks
[$name] = $callback;
3536 unset( $this->trxRecurringCallbacks
[$name] );
3541 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3543 * This method should not be used outside of Database/LoadBalancer
3545 * @param bool $suppress
3548 final public function setTrxEndCallbackSuppression( $suppress ) {
3549 $this->trxEndCallbacksSuppressed
= $suppress;
3553 * Actually consume and run any "on transaction idle/resolution" callbacks.
3555 * This method should not be used outside of Database/LoadBalancer
3557 * @param int $trigger IDatabase::TRIGGER_* constant
3558 * @return int Number of callbacks attempted
3562 public function runOnTransactionIdleCallbacks( $trigger ) {
3563 if ( $this->trxLevel
) { // sanity
3564 throw new DBUnexpectedError( $this, __METHOD__
. ': a transaction is still open.' );
3567 if ( $this->trxEndCallbacksSuppressed
) {
3572 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
3573 /** @var Exception $e */
3574 $e = null; // first exception
3575 do { // callbacks may add callbacks :)
3576 $callbacks = array_merge(
3577 $this->trxIdleCallbacks
,
3578 $this->trxEndCallbacks
// include "transaction resolution" callbacks
3580 $this->trxIdleCallbacks
= []; // consumed (and recursion guard)
3581 $this->trxEndCallbacks
= []; // consumed (recursion guard)
3582 foreach ( $callbacks as $callback ) {
3584 list( $phpCallback ) = $callback;
3585 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
3587 // @phan-suppress-next-line PhanParamTooManyCallable
3588 call_user_func( $phpCallback, $trigger, $this );
3589 } catch ( Exception
$ex ) {
3590 call_user_func( $this->errorLogger
, $ex );
3592 // Some callbacks may use startAtomic/endAtomic, so make sure
3593 // their transactions are ended so other callbacks don't fail
3594 if ( $this->trxLevel() ) {
3595 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
3599 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
3601 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
3605 } while ( count( $this->trxIdleCallbacks
) );
3607 if ( $e instanceof Exception
) {
3608 throw $e; // re-throw any first exception
3615 * Actually consume and run any "on transaction pre-commit" callbacks.
3617 * This method should not be used outside of Database/LoadBalancer
3620 * @return int Number of callbacks attempted
3623 public function runOnTransactionPreCommitCallbacks() {
3626 $e = null; // first exception
3627 do { // callbacks may add callbacks :)
3628 $callbacks = $this->trxPreCommitCallbacks
;
3629 $this->trxPreCommitCallbacks
= []; // consumed (and recursion guard)
3630 foreach ( $callbacks as $callback ) {
3633 list( $phpCallback ) = $callback;
3634 $phpCallback( $this );
3635 } catch ( Exception
$ex ) {
3636 ( $this->errorLogger
)( $ex );
3640 } while ( count( $this->trxPreCommitCallbacks
) );
3642 if ( $e instanceof Exception
) {
3643 throw $e; // re-throw any first exception
3650 * Actually run any "transaction listener" callbacks.
3652 * This method should not be used outside of Database/LoadBalancer
3654 * @param int $trigger IDatabase::TRIGGER_* constant
3658 public function runTransactionListenerCallbacks( $trigger ) {
3659 if ( $this->trxEndCallbacksSuppressed
) {
3663 /** @var Exception $e */
3664 $e = null; // first exception
3666 foreach ( $this->trxRecurringCallbacks
as $phpCallback ) {
3668 $phpCallback( $trigger, $this );
3669 } catch ( Exception
$ex ) {
3670 ( $this->errorLogger
)( $ex );
3675 if ( $e instanceof Exception
) {
3676 throw $e; // re-throw any first exception
3681 * Create a savepoint
3683 * This is used internally to implement atomic sections. It should not be
3687 * @param string $identifier Identifier for the savepoint
3688 * @param string $fname Calling function name
3690 protected function doSavepoint( $identifier, $fname ) {
3691 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3695 * Release a savepoint
3697 * This is used internally to implement atomic sections. It should not be
3701 * @param string $identifier Identifier for the savepoint
3702 * @param string $fname Calling function name
3704 protected function doReleaseSavepoint( $identifier, $fname ) {
3705 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3709 * Rollback to a savepoint
3711 * This is used internally to implement atomic sections. It should not be
3715 * @param string $identifier Identifier for the savepoint
3716 * @param string $fname Calling function name
3718 protected function doRollbackToSavepoint( $identifier, $fname ) {
3719 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3723 * @param string $fname
3726 private function nextSavepointId( $fname ) {
3727 $savepointId = self
::$SAVEPOINT_PREFIX . ++
$this->trxAtomicCounter
;
3728 if ( strlen( $savepointId ) > 30 ) {
3729 // 30 == Oracle's identifier length limit (pre 12c)
3730 // With a 22 character prefix, that puts the highest number at 99999999.
3731 throw new DBUnexpectedError(
3733 'There have been an excessively large number of atomic sections in a transaction'
3734 . " started by $this->trxFname (at $fname)"
3738 return $savepointId;
3741 final public function startAtomic(
3742 $fname = __METHOD__
, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3744 $savepointId = $cancelable === self
::ATOMIC_CANCELABLE ? self
::$NOT_APPLICABLE : null;
3746 if ( !$this->trxLevel
) {
3747 $this->begin( $fname, self
::TRANSACTION_INTERNAL
); // sets trxAutomatic
3748 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3749 // in all changes being in one transaction to keep requests transactional.
3750 if ( $this->getFlag( self
::DBO_TRX
) ) {
3751 // Since writes could happen in between the topmost atomic sections as part
3752 // of the transaction, those sections will need savepoints.
3753 $savepointId = $this->nextSavepointId( $fname );
3754 $this->doSavepoint( $savepointId, $fname );
3756 $this->trxAutomaticAtomic
= true;
3758 } elseif ( $cancelable === self
::ATOMIC_CANCELABLE
) {
3759 $savepointId = $this->nextSavepointId( $fname );
3760 $this->doSavepoint( $savepointId, $fname );
3763 $sectionId = new AtomicSectionIdentifier
;
3764 $this->trxAtomicLevels
[] = [ $fname, $sectionId, $savepointId ];
3765 $this->queryLogger
->debug( 'startAtomic: entering level ' .
3766 ( count( $this->trxAtomicLevels
) - 1 ) . " ($fname)" );
3771 final public function endAtomic( $fname = __METHOD__
) {
3772 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3773 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3776 // Check if the current section matches $fname
3777 $pos = count( $this->trxAtomicLevels
) - 1;
3778 list( $savedFname, $sectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3779 $this->queryLogger
->debug( "endAtomic: leaving level $pos ($fname)" );
3781 if ( $savedFname !== $fname ) {
3782 throw new DBUnexpectedError(
3784 "Invalid atomic section ended (got $fname but expected $savedFname)."
3788 // Remove the last section (no need to re-index the array)
3789 array_pop( $this->trxAtomicLevels
);
3791 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3792 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3793 } elseif ( $savepointId !== null && $savepointId !== self
::$NOT_APPLICABLE ) {
3794 $this->doReleaseSavepoint( $savepointId, $fname );
3797 // Hoist callback ownership for callbacks in the section that just ended;
3798 // all callbacks should have an owner that is present in trxAtomicLevels.
3799 $currentSectionId = $this->currentAtomicSectionId();
3800 if ( $currentSectionId ) {
3801 $this->reassignCallbacksForSection( $sectionId, $currentSectionId );
3805 final public function cancelAtomic(
3806 $fname = __METHOD__
, AtomicSectionIdentifier
$sectionId = null
3808 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3809 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3812 $excisedFnames = [];
3813 if ( $sectionId !== null ) {
3814 // Find the (last) section with the given $sectionId
3816 foreach ( $this->trxAtomicLevels
as $i => list( $asFname, $asId, $spId ) ) {
3817 if ( $asId === $sectionId ) {
3822 throw new DBUnexpectedError( $this, "Atomic section not found (for $fname)" );
3824 // Remove all descendant sections and re-index the array
3826 $len = count( $this->trxAtomicLevels
);
3827 for ( $i = $pos +
1; $i < $len; ++
$i ) {
3828 $excisedFnames[] = $this->trxAtomicLevels
[$i][0];
3829 $excisedIds[] = $this->trxAtomicLevels
[$i][1];
3831 $this->trxAtomicLevels
= array_slice( $this->trxAtomicLevels
, 0, $pos +
1 );
3832 $this->modifyCallbacksForCancel( $excisedIds );
3835 // Check if the current section matches $fname
3836 $pos = count( $this->trxAtomicLevels
) - 1;
3837 list( $savedFname, $savedSectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3839 if ( $excisedFnames ) {
3840 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname) " .
3841 "and descendants " . implode( ', ', $excisedFnames ) );
3843 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname)" );
3846 if ( $savedFname !== $fname ) {
3847 throw new DBUnexpectedError(
3849 "Invalid atomic section ended (got $fname but expected $savedFname)."
3853 // Remove the last section (no need to re-index the array)
3854 array_pop( $this->trxAtomicLevels
);
3855 $this->modifyCallbacksForCancel( [ $savedSectionId ] );
3857 if ( $savepointId !== null ) {
3858 // Rollback the transaction to the state just before this atomic section
3859 if ( $savepointId === self
::$NOT_APPLICABLE ) {
3860 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
3862 $this->doRollbackToSavepoint( $savepointId, $fname );
3863 $this->trxStatus
= self
::STATUS_TRX_OK
; // no exception; recovered
3864 $this->trxStatusIgnoredCause
= null;
3866 } elseif ( $this->trxStatus
> self
::STATUS_TRX_ERROR
) {
3867 // Put the transaction into an error state if it's not already in one
3868 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
3869 $this->trxStatusCause
= new DBUnexpectedError(
3871 "Uncancelable atomic section canceled (got $fname)."
3875 $this->affectedRowCount
= 0; // for the sake of consistency
3878 final public function doAtomicSection(
3879 $fname, callable
$callback, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3881 $sectionId = $this->startAtomic( $fname, $cancelable );
3883 $res = $callback( $this, $fname );
3884 } catch ( Exception
$e ) {
3885 $this->cancelAtomic( $fname, $sectionId );
3889 $this->endAtomic( $fname );
3894 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
3895 static $modes = [ self
::TRANSACTION_EXPLICIT
, self
::TRANSACTION_INTERNAL
];
3896 if ( !in_array( $mode, $modes, true ) ) {
3897 throw new DBUnexpectedError( $this, "$fname: invalid mode parameter '$mode'." );
3900 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3901 if ( $this->trxLevel
) {
3902 if ( $this->trxAtomicLevels
) {
3903 $levels = $this->flatAtomicSectionList();
3904 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
3905 throw new DBUnexpectedError( $this, $msg );
3906 } elseif ( !$this->trxAutomatic
) {
3907 $msg = "$fname: Explicit transaction already active (from {$this->trxFname}).";
3908 throw new DBUnexpectedError( $this, $msg );
3910 $msg = "$fname: Implicit transaction already active (from {$this->trxFname}).";
3911 throw new DBUnexpectedError( $this, $msg );
3913 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
3914 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
3915 throw new DBUnexpectedError( $this, $msg );
3918 $this->assertHasConnectionHandle();
3920 $this->doBegin( $fname );
3921 $this->trxStatus
= self
::STATUS_TRX_OK
;
3922 $this->trxStatusIgnoredCause
= null;
3923 $this->trxAtomicCounter
= 0;
3924 $this->trxTimestamp
= microtime( true );
3925 $this->trxFname
= $fname;
3926 $this->trxDoneWrites
= false;
3927 $this->trxAutomaticAtomic
= false;
3928 $this->trxAtomicLevels
= [];
3929 $this->trxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3930 $this->trxWriteDuration
= 0.0;
3931 $this->trxWriteQueryCount
= 0;
3932 $this->trxWriteAffectedRows
= 0;
3933 $this->trxWriteAdjDuration
= 0.0;
3934 $this->trxWriteAdjQueryCount
= 0;
3935 $this->trxWriteCallers
= [];
3936 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
3937 // Get an estimate of the replication lag before any such queries.
3938 $this->trxReplicaLag
= null; // clear cached value first
3939 $this->trxReplicaLag
= $this->getApproximateLagStatus()['lag'];
3940 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3941 // caller will think its OK to muck around with the transaction just because startAtomic()
3942 // has not yet completed (e.g. setting trxAtomicLevels).
3943 $this->trxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
3947 * Issues the BEGIN command to the database server.
3949 * @see Database::begin()
3950 * @param string $fname
3952 protected function doBegin( $fname ) {
3953 $this->query( 'BEGIN', $fname );
3954 $this->trxLevel
= 1;
3957 final public function commit( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
3958 static $modes = [ self
::FLUSHING_ONE
, self
::FLUSHING_ALL_PEERS
, self
::FLUSHING_INTERNAL
];
3959 if ( !in_array( $flush, $modes, true ) ) {
3960 throw new DBUnexpectedError( $this, "$fname: invalid flush parameter '$flush'." );
3963 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3964 // There are still atomic sections open; this cannot be ignored
3965 $levels = $this->flatAtomicSectionList();
3966 throw new DBUnexpectedError(
3968 "$fname: Got COMMIT while atomic sections $levels are still open."
3972 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3973 if ( !$this->trxLevel
) {
3974 return; // nothing to do
3975 } elseif ( !$this->trxAutomatic
) {
3976 throw new DBUnexpectedError(
3978 "$fname: Flushing an explicit transaction, getting out of sync."
3981 } elseif ( !$this->trxLevel
) {
3982 $this->queryLogger
->error(
3983 "$fname: No transaction to commit, something got out of sync." );
3984 return; // nothing to do
3985 } elseif ( $this->trxAutomatic
) {
3986 throw new DBUnexpectedError(
3988 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)."
3992 $this->assertHasConnectionHandle();
3994 $this->runOnTransactionPreCommitCallbacks();
3996 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
3997 $this->doCommit( $fname );
3998 $this->trxStatus
= self
::STATUS_TRX_NONE
;
4000 if ( $this->trxDoneWrites
) {
4001 $this->lastWriteTime
= microtime( true );
4002 $this->trxProfiler
->transactionWritingOut(
4004 $this->getDomainID(),
4007 $this->trxWriteAffectedRows
4011 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4012 if ( $flush !== self
::FLUSHING_ALL_PEERS
) {
4013 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
4014 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
4019 * Issues the COMMIT command to the database server.
4021 * @see Database::commit()
4022 * @param string $fname
4024 protected function doCommit( $fname ) {
4025 if ( $this->trxLevel
) {
4026 $this->query( 'COMMIT', $fname );
4027 $this->trxLevel
= 0;
4031 final public function rollback( $fname = __METHOD__
, $flush = '' ) {
4032 $trxActive = $this->trxLevel
;
4034 if ( $flush !== self
::FLUSHING_INTERNAL
4035 && $flush !== self
::FLUSHING_ALL_PEERS
4036 && $this->getFlag( self
::DBO_TRX
)
4038 throw new DBUnexpectedError(
4040 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)."
4045 $this->assertHasConnectionHandle();
4047 $this->doRollback( $fname );
4048 $this->trxStatus
= self
::STATUS_TRX_NONE
;
4049 $this->trxAtomicLevels
= [];
4050 // Estimate the RTT via a query now that trxStatus is OK
4051 $writeTime = $this->pingAndCalculateLastTrxApplyTime();
4053 if ( $this->trxDoneWrites
) {
4054 $this->trxProfiler
->transactionWritingOut(
4056 $this->getDomainID(),
4059 $this->trxWriteAffectedRows
4064 // Clear any commit-dependant callbacks. They might even be present
4065 // only due to transaction rounds, with no SQL transaction being active
4066 $this->trxIdleCallbacks
= [];
4067 $this->trxPreCommitCallbacks
= [];
4069 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4070 if ( $trxActive && $flush !== self
::FLUSHING_ALL_PEERS
) {
4072 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
4073 } catch ( Exception
$e ) {
4074 // already logged; finish and let LoadBalancer move on during mass-rollback
4077 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
4078 } catch ( Exception
$e ) {
4079 // already logged; let LoadBalancer move on during mass-rollback
4082 $this->affectedRowCount
= 0; // for the sake of consistency
4087 * Issues the ROLLBACK command to the database server.
4089 * @see Database::rollback()
4090 * @param string $fname
4092 protected function doRollback( $fname ) {
4093 if ( $this->trxLevel
) {
4094 # Disconnects cause rollback anyway, so ignore those errors
4095 $ignoreErrors = true;
4096 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
4097 $this->trxLevel
= 0;
4101 public function flushSnapshot( $fname = __METHOD__
) {
4102 if ( $this->writesOrCallbacksPending() ||
$this->explicitTrxActive() ) {
4103 // This only flushes transactions to clear snapshots, not to write data
4104 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4105 throw new DBUnexpectedError(
4107 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
4111 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4114 public function explicitTrxActive() {
4115 return $this->trxLevel
&& ( $this->trxAtomicLevels ||
!$this->trxAutomatic
);
4118 public function duplicateTableStructure(
4119 $oldName, $newName, $temporary = false, $fname = __METHOD__
4121 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4124 public function listTables( $prefix = null, $fname = __METHOD__
) {
4125 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4128 public function listViews( $prefix = null, $fname = __METHOD__
) {
4129 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4132 public function timestamp( $ts = 0 ) {
4133 $t = new ConvertibleTimestamp( $ts );
4134 // Let errors bubble up to avoid putting garbage in the DB
4135 return $t->getTimestamp( TS_MW
);
4138 public function timestampOrNull( $ts = null ) {
4139 if ( is_null( $ts ) ) {
4142 return $this->timestamp( $ts );
4146 public function affectedRows() {
4147 return ( $this->affectedRowCount
=== null )
4148 ?
$this->fetchAffectedRowCount() // default to driver value
4149 : $this->affectedRowCount
;
4153 * @return int Number of retrieved rows according to the driver
4155 abstract protected function fetchAffectedRowCount();
4158 * Take the result from a query, and wrap it in a ResultWrapper if
4159 * necessary. Boolean values are passed through as is, to indicate success
4160 * of write queries or failure.
4162 * Once upon a time, Database::query() returned a bare MySQL result
4163 * resource, and it was necessary to call this function to convert it to
4164 * a wrapper. Nowadays, raw database objects are never exposed to external
4165 * callers, so this is unnecessary in external code.
4167 * @param bool|ResultWrapper|resource $result
4168 * @return bool|ResultWrapper
4170 protected function resultObject( $result ) {
4173 } elseif ( $result instanceof ResultWrapper
) {
4175 } elseif ( $result === true ) {
4176 // Successful write query
4179 return new ResultWrapper( $this, $result );
4183 public function ping( &$rtt = null ) {
4184 // Avoid hitting the server if it was hit recently
4185 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::PING_TTL
) {
4186 if ( !func_num_args() ||
$this->rttEstimate
> 0 ) {
4187 $rtt = $this->rttEstimate
;
4188 return true; // don't care about $rtt
4192 // This will reconnect if possible or return false if not
4193 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
4194 $ok = ( $this->query( self
::PING_QUERY
, __METHOD__
, true ) !== false );
4195 $this->restoreFlags( self
::RESTORE_PRIOR
);
4198 $rtt = $this->rttEstimate
;
4205 * Close any existing (dead) database connection and open a new connection
4207 * @param string $fname
4208 * @return bool True if new connection is opened successfully, false if error
4210 protected function replaceLostConnection( $fname ) {
4211 $this->closeConnection();
4212 $this->opened
= false;
4213 $this->conn
= false;
4215 $this->handleSessionLossPreconnect();
4224 $this->tablePrefix()
4226 $this->lastPing
= microtime( true );
4229 $this->connLogger
->warning(
4230 $fname . ': lost connection to {dbserver}; reconnected',
4232 'dbserver' => $this->getServer(),
4233 'trace' => ( new RuntimeException() )->getTraceAsString()
4236 } catch ( DBConnectionError
$e ) {
4239 $this->connLogger
->error(
4240 $fname . ': lost connection to {dbserver} permanently',
4241 [ 'dbserver' => $this->getServer() ]
4245 $this->handleSessionLossPostconnect();
4250 public function getSessionLagStatus() {
4251 return $this->getRecordedTransactionLagStatus() ?
: $this->getApproximateLagStatus();
4255 * Get the replica DB lag when the current transaction started
4257 * This is useful when transactions might use snapshot isolation
4258 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
4259 * is this lag plus transaction duration. If they don't, it is still
4260 * safe to be pessimistic. This returns null if there is no transaction.
4262 * This returns null if the lag status for this transaction was not yet recorded.
4264 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
4267 final protected function getRecordedTransactionLagStatus() {
4268 return ( $this->trxLevel
&& $this->trxReplicaLag
!== null )
4269 ?
[ 'lag' => $this->trxReplicaLag
, 'since' => $this->trxTimestamp() ]
4274 * Get a replica DB lag estimate for this server
4276 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
4279 protected function getApproximateLagStatus() {
4281 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
4282 'since' => microtime( true )
4287 * Merge the result of getSessionLagStatus() for several DBs
4288 * using the most pessimistic values to estimate the lag of
4289 * any data derived from them in combination
4291 * This is information is useful for caching modules
4293 * @see WANObjectCache::set()
4294 * @see WANObjectCache::getWithSetCallback()
4296 * @param IDatabase $db1
4297 * @param IDatabase|null $db2 [optional]
4298 * @return array Map of values:
4299 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
4300 * - since: oldest UNIX timestamp of any of the DB lag estimates
4301 * - pending: whether any of the DBs have uncommitted changes
4305 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
4306 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
4307 foreach ( func_get_args() as $db ) {
4308 /** @var IDatabase $db */
4309 $status = $db->getSessionLagStatus();
4310 if ( $status['lag'] === false ) {
4311 $res['lag'] = false;
4312 } elseif ( $res['lag'] !== false ) {
4313 $res['lag'] = max( $res['lag'], $status['lag'] );
4315 $res['since'] = min( $res['since'], $status['since'] );
4316 $res['pending'] = $res['pending'] ?
: $db->writesPending();
4322 public function getLag() {
4326 public function maxListLen() {
4330 public function encodeBlob( $b ) {
4334 public function decodeBlob( $b ) {
4335 if ( $b instanceof Blob
) {
4341 public function setSessionOptions( array $options ) {
4344 public function sourceFile(
4346 callable
$lineCallback = null,
4347 callable
$resultCallback = null,
4349 callable
$inputCallback = null
4351 Wikimedia\
suppressWarnings();
4352 $fp = fopen( $filename, 'r' );
4353 Wikimedia\restoreWarnings
();
4355 if ( $fp === false ) {
4356 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
4360 $fname = __METHOD__
. "( $filename )";
4364 $error = $this->sourceStream(
4365 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
4366 } catch ( Exception
$e ) {
4376 public function setSchemaVars( $vars ) {
4377 $this->schemaVars
= $vars;
4380 public function sourceStream(
4382 callable
$lineCallback = null,
4383 callable
$resultCallback = null,
4384 $fname = __METHOD__
,
4385 callable
$inputCallback = null
4387 $delimiterReset = new ScopedCallback(
4388 function ( $delimiter ) {
4389 $this->delimiter
= $delimiter;
4391 [ $this->delimiter
]
4395 while ( !feof( $fp ) ) {
4396 if ( $lineCallback ) {
4397 call_user_func( $lineCallback );
4400 $line = trim( fgets( $fp ) );
4402 if ( $line == '' ) {
4406 if ( $line[0] == '-' && $line[1] == '-' ) {
4414 $done = $this->streamStatementEnd( $cmd, $line );
4418 if ( $done ||
feof( $fp ) ) {
4419 $cmd = $this->replaceVars( $cmd );
4421 if ( $inputCallback ) {
4422 $callbackResult = $inputCallback( $cmd );
4424 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
4425 $cmd = $callbackResult;
4430 $res = $this->query( $cmd, $fname );
4432 if ( $resultCallback ) {
4433 $resultCallback( $res, $this );
4436 if ( $res === false ) {
4437 $err = $this->lastError();
4439 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
4446 ScopedCallback
::consume( $delimiterReset );
4451 * Called by sourceStream() to check if we've reached a statement end
4453 * @param string &$sql SQL assembled so far
4454 * @param string &$newLine New line about to be added to $sql
4455 * @return bool Whether $newLine contains end of the statement
4457 public function streamStatementEnd( &$sql, &$newLine ) {
4458 if ( $this->delimiter
) {
4460 $newLine = preg_replace(
4461 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
4462 if ( $newLine != $prev ) {
4471 * Database independent variable replacement. Replaces a set of variables
4472 * in an SQL statement with their contents as given by $this->getSchemaVars().
4474 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
4476 * - '{$var}' should be used for text and is passed through the database's
4478 * - `{$var}` should be used for identifiers (e.g. table and database names).
4479 * It is passed through the database's addIdentifierQuotes method which
4480 * can be overridden if the database uses something other than backticks.
4481 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
4482 * database's tableName method.
4483 * - / *i* / passes the name that follows through the database's indexName method.
4484 * - In all other cases, / *$var* / is left unencoded. Except for table options,
4485 * its use should be avoided. In 1.24 and older, string encoding was applied.
4487 * @param string $ins SQL statement to replace variables in
4488 * @return string The new SQL statement with variables replaced
4490 protected function replaceVars( $ins ) {
4491 $vars = $this->getSchemaVars();
4492 return preg_replace_callback(
4494 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
4495 \'\{\$ (\w+) }\' | # 3. addQuotes
4496 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
4497 /\*\$ (\w+) \*/ # 5. leave unencoded
4499 function ( $m ) use ( $vars ) {
4500 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
4501 // check for both nonexistent keys *and* the empty string.
4502 if ( isset( $m[1] ) && $m[1] !== '' ) {
4503 if ( $m[1] === 'i' ) {
4504 return $this->indexName( $m[2] );
4506 return $this->tableName( $m[2] );
4508 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
4509 return $this->addQuotes( $vars[$m[3]] );
4510 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
4511 return $this->addIdentifierQuotes( $vars[$m[4]] );
4512 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
4513 return $vars[$m[5]];
4523 * Get schema variables. If none have been set via setSchemaVars(), then
4524 * use some defaults from the current object.
4528 protected function getSchemaVars() {
4529 if ( $this->schemaVars
) {
4530 return $this->schemaVars
;
4532 return $this->getDefaultSchemaVars();
4537 * Get schema variables to use if none have been set via setSchemaVars().
4539 * Override this in derived classes to provide variables for tables.sql
4540 * and SQL patch files.
4544 protected function getDefaultSchemaVars() {
4548 public function lockIsFree( $lockName, $method ) {
4549 // RDBMs methods for checking named locks may or may not count this thread itself.
4550 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4551 // the behavior choosen by the interface for this method.
4552 return !isset( $this->namedLocksHeld
[$lockName] );
4555 public function lock( $lockName, $method, $timeout = 5 ) {
4556 $this->namedLocksHeld
[$lockName] = 1;
4561 public function unlock( $lockName, $method ) {
4562 unset( $this->namedLocksHeld
[$lockName] );
4567 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4568 if ( $this->writesOrCallbacksPending() ) {
4569 // This only flushes transactions to clear snapshots, not to write data
4570 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4571 throw new DBUnexpectedError(
4573 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
4577 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4581 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4582 if ( $this->trxLevel() ) {
4583 // There is a good chance an exception was thrown, causing any early return
4584 // from the caller. Let any error handler get a chance to issue rollback().
4585 // If there isn't one, let the error bubble up and trigger server-side rollback.
4586 $this->onTransactionResolution(
4587 function () use ( $lockKey, $fname ) {
4588 $this->unlock( $lockKey, $fname );
4593 $this->unlock( $lockKey, $fname );
4597 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4602 public function namedLocksEnqueue() {
4606 public function tableLocksHaveTransactionScope() {
4610 final public function lockTables( array $read, array $write, $method ) {
4611 if ( $this->writesOrCallbacksPending() ) {
4612 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
4615 if ( $this->tableLocksHaveTransactionScope() ) {
4616 $this->startAtomic( $method );
4619 return $this->doLockTables( $read, $write, $method );
4623 * Helper function for lockTables() that handles the actual table locking
4625 * @param array $read Array of tables to lock for read access
4626 * @param array $write Array of tables to lock for write access
4627 * @param string $method Name of caller
4630 protected function doLockTables( array $read, array $write, $method ) {
4634 final public function unlockTables( $method ) {
4635 if ( $this->tableLocksHaveTransactionScope() ) {
4636 $this->endAtomic( $method );
4638 return true; // locks released on COMMIT/ROLLBACK
4641 return $this->doUnlockTables( $method );
4645 * Helper function for unlockTables() that handles the actual table unlocking
4647 * @param string $method Name of caller
4650 protected function doUnlockTables( $method ) {
4656 * @param string $tableName
4657 * @param string $fName
4658 * @return bool|ResultWrapper
4661 public function dropTable( $tableName, $fName = __METHOD__
) {
4662 if ( !$this->tableExists( $tableName, $fName ) ) {
4665 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4667 return $this->query( $sql, $fName );
4670 public function getInfinity() {
4674 public function encodeExpiry( $expiry ) {
4675 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
4676 ?
$this->getInfinity()
4677 : $this->timestamp( $expiry );
4680 public function decodeExpiry( $expiry, $format = TS_MW
) {
4681 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
4685 return ConvertibleTimestamp
::convert( $format, $expiry );
4688 public function setBigSelects( $value = true ) {
4692 public function isReadOnly() {
4693 return ( $this->getReadOnlyReason() !== false );
4697 * @return string|bool Reason this DB is read-only or false if it is not
4699 protected function getReadOnlyReason() {
4700 $reason = $this->getLBInfo( 'readOnlyReason' );
4702 return is_string( $reason ) ?
$reason : false;
4705 public function setTableAliases( array $aliases ) {
4706 $this->tableAliases
= $aliases;
4709 public function setIndexAliases( array $aliases ) {
4710 $this->indexAliases
= $aliases;
4718 protected function hasFlags( $field, $flags ) {
4719 return ( ( $field & $flags ) === $flags );
4723 * Get the underlying binding connection handle
4725 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4726 * This catches broken callers than catch and ignore disconnection exceptions.
4727 * Unlike checking isOpen(), this is safe to call inside of open().
4730 * @throws DBUnexpectedError
4733 protected function getBindingHandle() {
4734 if ( !$this->conn
) {
4735 throw new DBUnexpectedError(
4737 'DB connection was already closed or the connection dropped.'
4748 public function __toString() {
4749 return (string)$this->conn
;
4753 * Make sure that copies do not share the same client binding handle
4754 * @throws DBConnectionError
4756 public function __clone() {
4757 $this->connLogger
->warning(
4758 "Cloning " . static::class . " is not recommended; forking connection:\n" .
4759 ( new RuntimeException() )->getTraceAsString()
4762 if ( $this->isOpen() ) {
4763 // Open a new connection resource without messing with the old one
4764 $this->opened
= false;
4765 $this->conn
= false;
4766 $this->trxEndCallbacks
= []; // don't copy
4767 $this->handleSessionLossPreconnect(); // no trx or locks anymore
4774 $this->tablePrefix()
4776 $this->lastPing
= microtime( true );
4781 * Called by serialize. Throw an exception when DB connection is serialized.
4782 * This causes problems on some database engines because the connection is
4783 * not restored on unserialize.
4785 public function __sleep() {
4786 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4787 'the connection is not restored on wakeup.' );
4791 * Run a few simple sanity checks and close dangling connections
4793 public function __destruct() {
4794 if ( $this->trxLevel
&& $this->trxDoneWrites
) {
4795 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})." );
4798 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4799 if ( $danglingWriters ) {
4800 $fnames = implode( ', ', $danglingWriters );
4801 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
4804 if ( $this->conn
) {
4805 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4806 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4807 Wikimedia\
suppressWarnings();
4808 $this->closeConnection();
4809 Wikimedia\restoreWarnings
();
4810 $this->conn
= false;
4811 $this->opened
= false;
4817 * @deprecated since 1.28
4819 class_alias( Database
::class, 'DatabaseBase' );
4822 * @deprecated since 1.29
4824 class_alias( Database
::class, 'Database' );