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[lhc/web/wiklou.git] / includes / libs / rdbms / database / Database.php
1 <?php
2 /**
3 * @defgroup Database Database
4 *
5 * This file deals with database interface functions
6 * and query specifics/optimisations.
7 *
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.
12 *
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.
17 *
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
22 *
23 * @file
24 * @ingroup Database
25 */
26 namespace Wikimedia\Rdbms;
27
28 use Psr\Log\LoggerAwareInterface;
29 use Psr\Log\LoggerInterface;
30 use Psr\Log\NullLogger;
31 use Wikimedia\ScopedCallback;
32 use Wikimedia\Timestamp\ConvertibleTimestamp;
33 use Wikimedia;
34 use BagOStuff;
35 use HashBagOStuff;
36 use LogicException;
37 use InvalidArgumentException;
38 use UnexpectedValueException;
39 use Exception;
40 use RuntimeException;
41
42 /**
43 * Relational database abstraction object
44 *
45 * @ingroup Database
46 * @since 1.28
47 */
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;
55
56 /** How long before it is worth doing a dummy query to test the connection */
57 const PING_TTL = 1.0;
58 const PING_QUERY = 'SELECT 1 AS ping';
59
60 const TINY_WRITE_SEC = 0.010;
61 const SLOW_WRITE_SEC = 0.500;
62 const SMALL_WRITE_ROWS = 100;
63
64 /** @var string Whether lock granularity is on the level of the entire database */
65 const ATTR_DB_LEVEL_LOCKING = 'db-level-locking';
66
67 /** @var int New Database instance will not be connected yet when returned */
68 const NEW_UNCONNECTED = 0;
69 /** @var int New Database instance will already be connected when returned */
70 const NEW_CONNECTED = 1;
71
72 /** @var string SQL query */
73 protected $lastQuery = '';
74 /** @var float|bool UNIX timestamp of last write query */
75 protected $lastWriteTime = false;
76 /** @var string|bool */
77 protected $phpError = false;
78 /** @var string Server that this instance is currently connected to */
79 protected $server;
80 /** @var string User that this instance is currently connected under the name of */
81 protected $user;
82 /** @var string Password used to establish the current connection */
83 protected $password;
84 /** @var string Database that this instance is currently connected to */
85 protected $dbName;
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 */
91 protected $cliMode;
92 /** @var string Agent name for query profiling */
93 protected $agent;
94 /** @var array Parameters used by initConnection() to establish a connection */
95 protected $connectionParams = [];
96 /** @var BagOStuff APC cache */
97 protected $srvCache;
98 /** @var LoggerInterface */
99 protected $connLogger;
100 /** @var LoggerInterface */
101 protected $queryLogger;
102 /** @var callback Error logging callback */
103 protected $errorLogger;
104
105 /** @var resource|null Database connection */
106 protected $conn = null;
107 /** @var bool */
108 protected $opened = false;
109
110 /** @var array[] List of (callable, method name) */
111 protected $trxIdleCallbacks = [];
112 /** @var array[] List of (callable, method name) */
113 protected $trxPreCommitCallbacks = [];
114 /** @var array[] List of (callable, method name) */
115 protected $trxEndCallbacks = [];
116 /** @var callable[] Map of (name => callable) */
117 protected $trxRecurringCallbacks = [];
118 /** @var bool Whether to suppress triggering of transaction end callbacks */
119 protected $trxEndCallbacksSuppressed = false;
120
121 /** @var string */
122 protected $tablePrefix = '';
123 /** @var string */
124 protected $schema = '';
125 /** @var int */
126 protected $flags;
127 /** @var array */
128 protected $lbInfo = [];
129 /** @var array|bool */
130 protected $schemaVars = false;
131 /** @var array */
132 protected $sessionVars = [];
133 /** @var array|null */
134 protected $preparedArgs;
135 /** @var string|bool|null Stashed value of html_errors INI setting */
136 protected $htmlErrors;
137 /** @var string */
138 protected $delimiter = ';';
139 /** @var DatabaseDomain */
140 protected $currentDomain;
141 /** @var integer|null Rows affected by the last query to query() or its CRUD wrappers */
142 protected $affectedRowCount;
143
144 /**
145 * @var int Transaction status
146 */
147 protected $trxStatus = self::STATUS_TRX_NONE;
148 /**
149 * @var Exception|null The last error that caused the status to become STATUS_TRX_ERROR
150 */
151 protected $trxStatusCause;
152 /**
153 * Either 1 if a transaction is active or 0 otherwise.
154 * The other Trx fields may not be meaningfull if this is 0.
155 *
156 * @var int
157 */
158 protected $trxLevel = 0;
159 /**
160 * Either a short hexidecimal string if a transaction is active or ""
161 *
162 * @var string
163 * @see Database::trxLevel
164 */
165 protected $trxShortId = '';
166 /**
167 * The UNIX time that the transaction started. Callers can assume that if
168 * snapshot isolation is used, then the data is *at least* up to date to that
169 * point (possibly more up-to-date since the first SELECT defines the snapshot).
170 *
171 * @var float|null
172 * @see Database::trxLevel
173 */
174 private $trxTimestamp = null;
175 /** @var float Lag estimate at the time of BEGIN */
176 private $trxReplicaLag = null;
177 /**
178 * Remembers the function name given for starting the most recent transaction via begin().
179 * Used to provide additional context for error reporting.
180 *
181 * @var string
182 * @see Database::trxLevel
183 */
184 private $trxFname = null;
185 /**
186 * Record if possible write queries were done in the last transaction started
187 *
188 * @var bool
189 * @see Database::trxLevel
190 */
191 private $trxDoneWrites = false;
192 /**
193 * Record if the current transaction was started implicitly due to DBO_TRX being set.
194 *
195 * @var bool
196 * @see Database::trxLevel
197 */
198 private $trxAutomatic = false;
199 /**
200 * Counter for atomic savepoint identifiers. Reset when a new transaction begins.
201 *
202 * @var int
203 */
204 private $trxAtomicCounter = 0;
205 /**
206 * Array of levels of atomicity within transactions
207 *
208 * @var array
209 */
210 private $trxAtomicLevels = [];
211 /**
212 * Record if the current transaction was started implicitly by Database::startAtomic
213 *
214 * @var bool
215 */
216 private $trxAutomaticAtomic = false;
217 /**
218 * Track the write query callers of the current transaction
219 *
220 * @var string[]
221 */
222 private $trxWriteCallers = [];
223 /**
224 * @var float Seconds spent in write queries for the current transaction
225 */
226 private $trxWriteDuration = 0.0;
227 /**
228 * @var int Number of write queries for the current transaction
229 */
230 private $trxWriteQueryCount = 0;
231 /**
232 * @var int Number of rows affected by write queries for the current transaction
233 */
234 private $trxWriteAffectedRows = 0;
235 /**
236 * @var float Like trxWriteQueryCount but excludes lock-bound, easy to replicate, queries
237 */
238 private $trxWriteAdjDuration = 0.0;
239 /**
240 * @var int Number of write queries counted in trxWriteAdjDuration
241 */
242 private $trxWriteAdjQueryCount = 0;
243 /**
244 * @var float RTT time estimate
245 */
246 private $rttEstimate = 0.0;
247
248 /** @var array Map of (name => 1) for locks obtained via lock() */
249 private $namedLocksHeld = [];
250 /** @var array Map of (table name => 1) for TEMPORARY tables */
251 protected $sessionTempTables = [];
252
253 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
254 private $lazyMasterHandle;
255
256 /** @var float UNIX timestamp */
257 protected $lastPing = 0.0;
258
259 /** @var int[] Prior flags member variable values */
260 private $priorFlags = [];
261
262 /** @var object|string Class name or object With profileIn/profileOut methods */
263 protected $profiler;
264 /** @var TransactionProfiler */
265 protected $trxProfiler;
266
267 /** @var int */
268 protected $nonNativeInsertSelectBatchSize = 10000;
269
270 /** @var int Transaction is in a error state requiring a full or savepoint rollback */
271 const STATUS_TRX_ERROR = 1;
272 /** @var int Transaction is active and in a normal state */
273 const STATUS_TRX_OK = 2;
274 /** @var int No transaction is active */
275 const STATUS_TRX_NONE = 3;
276
277 /**
278 * @note: exceptions for missing libraries/drivers should be thrown in initConnection()
279 * @param array $params Parameters passed from Database::factory()
280 */
281 protected function __construct( array $params ) {
282 foreach ( [ 'host', 'user', 'password', 'dbname' ] as $name ) {
283 $this->connectionParams[$name] = $params[$name];
284 }
285
286 $this->schema = $params['schema'];
287 $this->tablePrefix = $params['tablePrefix'];
288
289 $this->cliMode = $params['cliMode'];
290 // Agent name is added to SQL queries in a comment, so make sure it can't break out
291 $this->agent = str_replace( '/', '-', $params['agent'] );
292
293 $this->flags = $params['flags'];
294 if ( $this->flags & self::DBO_DEFAULT ) {
295 if ( $this->cliMode ) {
296 $this->flags &= ~self::DBO_TRX;
297 } else {
298 $this->flags |= self::DBO_TRX;
299 }
300 }
301 // Disregard deprecated DBO_IGNORE flag (T189999)
302 $this->flags &= ~self::DBO_IGNORE;
303
304 $this->sessionVars = $params['variables'];
305
306 $this->srvCache = isset( $params['srvCache'] )
307 ? $params['srvCache']
308 : new HashBagOStuff();
309
310 $this->profiler = $params['profiler'];
311 $this->trxProfiler = $params['trxProfiler'];
312 $this->connLogger = $params['connLogger'];
313 $this->queryLogger = $params['queryLogger'];
314 $this->errorLogger = $params['errorLogger'];
315
316 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
317 $this->nonNativeInsertSelectBatchSize = $params['nonNativeInsertSelectBatchSize'];
318 }
319
320 // Set initial dummy domain until open() sets the final DB/prefix
321 $this->currentDomain = DatabaseDomain::newUnspecified();
322 }
323
324 /**
325 * Initialize the connection to the database over the wire (or to local files)
326 *
327 * @throws LogicException
328 * @throws InvalidArgumentException
329 * @throws DBConnectionError
330 * @since 1.31
331 */
332 final public function initConnection() {
333 if ( $this->isOpen() ) {
334 throw new LogicException( __METHOD__ . ': already connected.' );
335 }
336 // Establish the connection
337 $this->doInitConnection();
338 // Set the domain object after open() sets the relevant fields
339 if ( $this->dbName != '' ) {
340 // Domains with server scope but a table prefix are not used by IDatabase classes
341 $this->currentDomain = new DatabaseDomain( $this->dbName, null, $this->tablePrefix );
342 }
343 }
344
345 /**
346 * Actually connect to the database over the wire (or to local files)
347 *
348 * @throws InvalidArgumentException
349 * @throws DBConnectionError
350 * @since 1.31
351 */
352 protected function doInitConnection() {
353 if ( strlen( $this->connectionParams['user'] ) ) {
354 $this->open(
355 $this->connectionParams['host'],
356 $this->connectionParams['user'],
357 $this->connectionParams['password'],
358 $this->connectionParams['dbname']
359 );
360 } else {
361 throw new InvalidArgumentException( "No database user provided." );
362 }
363 }
364
365 /**
366 * Construct a Database subclass instance given a database type and parameters
367 *
368 * This also connects to the database immediately upon object construction
369 *
370 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
371 * @param array $p Parameter map with keys:
372 * - host : The hostname of the DB server
373 * - user : The name of the database user the client operates under
374 * - password : The password for the database user
375 * - dbname : The name of the database to use where queries do not specify one.
376 * The database must exist or an error might be thrown. Setting this to the empty string
377 * will avoid any such errors and make the handle have no implicit database scope. This is
378 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
379 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
380 * in which user names and such are defined, e.g. users are database-specific in Postgres.
381 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
382 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
383 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
384 * recognized in queries. This can be used in place of schemas for handle site farms.
385 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
386 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
387 * flag in place UNLESS this this database simply acts as a key/value store.
388 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
389 * 'mysqli' driver; the old one 'mysql' has been removed.
390 * - variables: Optional map of session variables to set after connecting. This can be
391 * used to adjust lock timeouts or encoding modes and the like.
392 * - connLogger: Optional PSR-3 logger interface instance.
393 * - queryLogger: Optional PSR-3 logger interface instance.
394 * - profiler: Optional class name or object with profileIn()/profileOut() methods.
395 * These will be called in query(), using a simplified version of the SQL that also
396 * includes the agent as a SQL comment.
397 * - trxProfiler: Optional TransactionProfiler instance.
398 * - errorLogger: Optional callback that takes an Exception and logs it.
399 * - cliMode: Whether to consider the execution context that of a CLI script.
400 * - agent: Optional name used to identify the end-user in query profiling/logging.
401 * - srvCache: Optional BagOStuff instance to an APC-style cache.
402 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
403 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
404 * @return Database|null If the database driver or extension cannot be found
405 * @throws InvalidArgumentException If the database driver or extension cannot be found
406 * @since 1.18
407 */
408 final public static function factory( $dbType, $p = [], $connect = self::NEW_CONNECTED ) {
409 $class = self::getClass( $dbType, isset( $p['driver'] ) ? $p['driver'] : null );
410
411 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase::class ) ) {
412 // Resolve some defaults for b/c
413 $p['host'] = isset( $p['host'] ) ? $p['host'] : false;
414 $p['user'] = isset( $p['user'] ) ? $p['user'] : false;
415 $p['password'] = isset( $p['password'] ) ? $p['password'] : false;
416 $p['dbname'] = isset( $p['dbname'] ) ? $p['dbname'] : false;
417 $p['flags'] = isset( $p['flags'] ) ? $p['flags'] : 0;
418 $p['variables'] = isset( $p['variables'] ) ? $p['variables'] : [];
419 $p['tablePrefix'] = isset( $p['tablePrefix'] ) ? $p['tablePrefix'] : '';
420 $p['schema'] = isset( $p['schema'] ) ? $p['schema'] : '';
421 $p['cliMode'] = isset( $p['cliMode'] )
422 ? $p['cliMode']
423 : ( PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg' );
424 $p['agent'] = isset( $p['agent'] ) ? $p['agent'] : '';
425 if ( !isset( $p['connLogger'] ) ) {
426 $p['connLogger'] = new NullLogger();
427 }
428 if ( !isset( $p['queryLogger'] ) ) {
429 $p['queryLogger'] = new NullLogger();
430 }
431 $p['profiler'] = isset( $p['profiler'] ) ? $p['profiler'] : null;
432 if ( !isset( $p['trxProfiler'] ) ) {
433 $p['trxProfiler'] = new TransactionProfiler();
434 }
435 if ( !isset( $p['errorLogger'] ) ) {
436 $p['errorLogger'] = function ( Exception $e ) {
437 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING );
438 };
439 }
440
441 /** @var Database $conn */
442 $conn = new $class( $p );
443 if ( $connect == self::NEW_CONNECTED ) {
444 $conn->initConnection();
445 }
446 } else {
447 $conn = null;
448 }
449
450 return $conn;
451 }
452
453 /**
454 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
455 * @param string|null $driver Optional name of a specific DB client driver
456 * @return array Map of (Database::ATTRIBUTE_* constant => value) for all such constants
457 * @throws InvalidArgumentException
458 * @since 1.31
459 */
460 final public static function attributesFromType( $dbType, $driver = null ) {
461 static $defaults = [ self::ATTR_DB_LEVEL_LOCKING => false ];
462
463 $class = self::getClass( $dbType, $driver );
464
465 return call_user_func( [ $class, 'getAttributes' ] ) + $defaults;
466 }
467
468 /**
469 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
470 * @param string|null $driver Optional name of a specific DB client driver
471 * @return string Database subclass name to use
472 * @throws InvalidArgumentException
473 */
474 private static function getClass( $dbType, $driver = null ) {
475 // For database types with built-in support, the below maps type to IDatabase
476 // implementations. For types with multipe driver implementations (PHP extensions),
477 // an array can be used, keyed by extension name. In case of an array, the
478 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
479 // we auto-detect the first available driver. For types without built-in support,
480 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
481 static $builtinTypes = [
482 'mssql' => DatabaseMssql::class,
483 'mysql' => [ 'mysqli' => DatabaseMysqli::class ],
484 'sqlite' => DatabaseSqlite::class,
485 'postgres' => DatabasePostgres::class,
486 ];
487
488 $dbType = strtolower( $dbType );
489 $class = false;
490
491 if ( isset( $builtinTypes[$dbType] ) ) {
492 $possibleDrivers = $builtinTypes[$dbType];
493 if ( is_string( $possibleDrivers ) ) {
494 $class = $possibleDrivers;
495 } else {
496 if ( (string)$driver !== '' ) {
497 if ( !isset( $possibleDrivers[$driver] ) ) {
498 throw new InvalidArgumentException( __METHOD__ .
499 " type '$dbType' does not support driver '{$driver}'" );
500 } else {
501 $class = $possibleDrivers[$driver];
502 }
503 } else {
504 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
505 if ( extension_loaded( $posDriver ) ) {
506 $class = $possibleClass;
507 break;
508 }
509 }
510 }
511 }
512 } else {
513 $class = 'Database' . ucfirst( $dbType );
514 }
515
516 if ( $class === false ) {
517 throw new InvalidArgumentException( __METHOD__ .
518 " no viable database extension found for type '$dbType'" );
519 }
520
521 return $class;
522 }
523
524 /**
525 * @return array Map of (Database::ATTRIBUTE_* constant => value
526 * @since 1.31
527 */
528 protected static function getAttributes() {
529 return [];
530 }
531
532 /**
533 * Set the PSR-3 logger interface to use for query logging. (The logger
534 * interfaces for connection logging and error logging can be set with the
535 * constructor.)
536 *
537 * @param LoggerInterface $logger
538 */
539 public function setLogger( LoggerInterface $logger ) {
540 $this->queryLogger = $logger;
541 }
542
543 public function getServerInfo() {
544 return $this->getServerVersion();
545 }
546
547 public function bufferResults( $buffer = null ) {
548 $res = !$this->getFlag( self::DBO_NOBUFFER );
549 if ( $buffer !== null ) {
550 $buffer
551 ? $this->clearFlag( self::DBO_NOBUFFER )
552 : $this->setFlag( self::DBO_NOBUFFER );
553 }
554
555 return $res;
556 }
557
558 public function trxLevel() {
559 return $this->trxLevel;
560 }
561
562 public function trxTimestamp() {
563 return $this->trxLevel ? $this->trxTimestamp : null;
564 }
565
566 /**
567 * @return int One of the STATUS_TRX_* class constants
568 * @since 1.31
569 */
570 public function trxStatus() {
571 return $this->trxStatus;
572 }
573
574 public function tablePrefix( $prefix = null ) {
575 $old = $this->tablePrefix;
576 if ( $prefix !== null ) {
577 $this->tablePrefix = $prefix;
578 $this->currentDomain = ( $this->dbName != '' )
579 ? new DatabaseDomain( $this->dbName, null, $this->tablePrefix )
580 : DatabaseDomain::newUnspecified();
581 }
582
583 return $old;
584 }
585
586 public function dbSchema( $schema = null ) {
587 $old = $this->schema;
588 if ( $schema !== null ) {
589 $this->schema = $schema;
590 }
591
592 return $old;
593 }
594
595 public function getLBInfo( $name = null ) {
596 if ( is_null( $name ) ) {
597 return $this->lbInfo;
598 } else {
599 if ( array_key_exists( $name, $this->lbInfo ) ) {
600 return $this->lbInfo[$name];
601 } else {
602 return null;
603 }
604 }
605 }
606
607 public function setLBInfo( $name, $value = null ) {
608 if ( is_null( $value ) ) {
609 $this->lbInfo = $name;
610 } else {
611 $this->lbInfo[$name] = $value;
612 }
613 }
614
615 public function setLazyMasterHandle( IDatabase $conn ) {
616 $this->lazyMasterHandle = $conn;
617 }
618
619 /**
620 * @return IDatabase|null
621 * @see setLazyMasterHandle()
622 * @since 1.27
623 */
624 protected function getLazyMasterHandle() {
625 return $this->lazyMasterHandle;
626 }
627
628 public function implicitGroupby() {
629 return true;
630 }
631
632 public function implicitOrderby() {
633 return true;
634 }
635
636 public function lastQuery() {
637 return $this->lastQuery;
638 }
639
640 public function doneWrites() {
641 return (bool)$this->lastWriteTime;
642 }
643
644 public function lastDoneWrites() {
645 return $this->lastWriteTime ?: false;
646 }
647
648 public function writesPending() {
649 return $this->trxLevel && $this->trxDoneWrites;
650 }
651
652 public function writesOrCallbacksPending() {
653 return $this->trxLevel && (
654 $this->trxDoneWrites ||
655 $this->trxIdleCallbacks ||
656 $this->trxPreCommitCallbacks ||
657 $this->trxEndCallbacks
658 );
659 }
660
661 /**
662 * @return string|null
663 */
664 final protected function getTransactionRoundId() {
665 // If transaction round participation is enabled, see if one is active
666 if ( $this->getFlag( self::DBO_TRX ) ) {
667 $id = $this->getLBInfo( 'trxRoundId' );
668
669 return is_string( $id ) ? $id : null;
670 }
671
672 return null;
673 }
674
675 public function pendingWriteQueryDuration( $type = self::ESTIMATE_TOTAL ) {
676 if ( !$this->trxLevel ) {
677 return false;
678 } elseif ( !$this->trxDoneWrites ) {
679 return 0.0;
680 }
681
682 switch ( $type ) {
683 case self::ESTIMATE_DB_APPLY:
684 $this->ping( $rtt );
685 $rttAdjTotal = $this->trxWriteAdjQueryCount * $rtt;
686 $applyTime = max( $this->trxWriteAdjDuration - $rttAdjTotal, 0 );
687 // For omitted queries, make them count as something at least
688 $omitted = $this->trxWriteQueryCount - $this->trxWriteAdjQueryCount;
689 $applyTime += self::TINY_WRITE_SEC * $omitted;
690
691 return $applyTime;
692 default: // everything
693 return $this->trxWriteDuration;
694 }
695 }
696
697 public function pendingWriteCallers() {
698 return $this->trxLevel ? $this->trxWriteCallers : [];
699 }
700
701 public function pendingWriteRowsAffected() {
702 return $this->trxWriteAffectedRows;
703 }
704
705 /**
706 * Get the list of method names that have pending write queries or callbacks
707 * for this transaction
708 *
709 * @return array
710 */
711 protected function pendingWriteAndCallbackCallers() {
712 if ( !$this->trxLevel ) {
713 return [];
714 }
715
716 $fnames = $this->trxWriteCallers;
717 foreach ( [
718 $this->trxIdleCallbacks,
719 $this->trxPreCommitCallbacks,
720 $this->trxEndCallbacks
721 ] as $callbacks ) {
722 foreach ( $callbacks as $callback ) {
723 $fnames[] = $callback[1];
724 }
725 }
726
727 return $fnames;
728 }
729
730 /**
731 * @return string
732 */
733 private function flatAtomicSectionList() {
734 return array_reduce( $this->trxAtomicLevels, function ( $accum, $v ) {
735 return $accum === null ? $v[0] : "$accum, " . $v[0];
736 } );
737 }
738
739 public function isOpen() {
740 return $this->opened;
741 }
742
743 public function setFlag( $flag, $remember = self::REMEMBER_NOTHING ) {
744 if ( ( $flag & self::DBO_IGNORE ) ) {
745 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
746 }
747
748 if ( $remember === self::REMEMBER_PRIOR ) {
749 array_push( $this->priorFlags, $this->flags );
750 }
751 $this->flags |= $flag;
752 }
753
754 public function clearFlag( $flag, $remember = self::REMEMBER_NOTHING ) {
755 if ( ( $flag & self::DBO_IGNORE ) ) {
756 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
757 }
758
759 if ( $remember === self::REMEMBER_PRIOR ) {
760 array_push( $this->priorFlags, $this->flags );
761 }
762 $this->flags &= ~$flag;
763 }
764
765 public function restoreFlags( $state = self::RESTORE_PRIOR ) {
766 if ( !$this->priorFlags ) {
767 return;
768 }
769
770 if ( $state === self::RESTORE_INITIAL ) {
771 $this->flags = reset( $this->priorFlags );
772 $this->priorFlags = [];
773 } else {
774 $this->flags = array_pop( $this->priorFlags );
775 }
776 }
777
778 public function getFlag( $flag ) {
779 return !!( $this->flags & $flag );
780 }
781
782 /**
783 * @param string $name Class field name
784 * @return mixed
785 * @deprecated Since 1.28
786 */
787 public function getProperty( $name ) {
788 return $this->$name;
789 }
790
791 public function getDomainID() {
792 return $this->currentDomain->getId();
793 }
794
795 final public function getWikiID() {
796 return $this->getDomainID();
797 }
798
799 /**
800 * Get information about an index into an object
801 * @param string $table Table name
802 * @param string $index Index name
803 * @param string $fname Calling function name
804 * @return mixed Database-specific index description class or false if the index does not exist
805 */
806 abstract function indexInfo( $table, $index, $fname = __METHOD__ );
807
808 /**
809 * Wrapper for addslashes()
810 *
811 * @param string $s String to be slashed.
812 * @return string Slashed string.
813 */
814 abstract function strencode( $s );
815
816 /**
817 * Set a custom error handler for logging errors during database connection
818 */
819 protected function installErrorHandler() {
820 $this->phpError = false;
821 $this->htmlErrors = ini_set( 'html_errors', '0' );
822 set_error_handler( [ $this, 'connectionErrorLogger' ] );
823 }
824
825 /**
826 * Restore the previous error handler and return the last PHP error for this DB
827 *
828 * @return bool|string
829 */
830 protected function restoreErrorHandler() {
831 restore_error_handler();
832 if ( $this->htmlErrors !== false ) {
833 ini_set( 'html_errors', $this->htmlErrors );
834 }
835
836 return $this->getLastPHPError();
837 }
838
839 /**
840 * @return string|bool Last PHP error for this DB (typically connection errors)
841 */
842 protected function getLastPHPError() {
843 if ( $this->phpError ) {
844 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->phpError );
845 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
846
847 return $error;
848 }
849
850 return false;
851 }
852
853 /**
854 * Error handler for logging errors during database connection
855 * This method should not be used outside of Database classes
856 *
857 * @param int $errno
858 * @param string $errstr
859 */
860 public function connectionErrorLogger( $errno, $errstr ) {
861 $this->phpError = $errstr;
862 }
863
864 /**
865 * Create a log context to pass to PSR-3 logger functions.
866 *
867 * @param array $extras Additional data to add to context
868 * @return array
869 */
870 protected function getLogContext( array $extras = [] ) {
871 return array_merge(
872 [
873 'db_server' => $this->server,
874 'db_name' => $this->dbName,
875 'db_user' => $this->user,
876 ],
877 $extras
878 );
879 }
880
881 final public function close() {
882 $exception = null; // error to throw after disconnecting
883
884 if ( $this->conn ) {
885 // Resolve any dangling transaction first
886 if ( $this->trxLevel ) {
887 // Meaningful transactions should ideally have been resolved by now
888 if ( $this->writesOrCallbacksPending() ) {
889 $this->queryLogger->warning(
890 __METHOD__ . ": writes or callbacks still pending.",
891 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
892 );
893 // Cannot let incomplete atomic sections be committed
894 if ( $this->trxAtomicLevels ) {
895 $levels = $this->flatAtomicSectionList();
896 $exception = new DBUnexpectedError(
897 $this,
898 __METHOD__ . ": atomic sections $levels are still open."
899 );
900 // Check if it is possible to properly commit and trigger callbacks
901 } elseif ( $this->trxEndCallbacksSuppressed ) {
902 $exception = new DBUnexpectedError(
903 $this,
904 __METHOD__ . ': callbacks are suppressed; cannot properly commit.'
905 );
906 }
907 }
908 // Commit or rollback the changes and run any callbacks as needed
909 if ( $this->trxStatus === self::STATUS_TRX_OK && !$exception ) {
910 $this->commit( __METHOD__, self::TRANSACTION_INTERNAL );
911 } else {
912 $this->rollback( __METHOD__, self::TRANSACTION_INTERNAL );
913 }
914 }
915 // Close the actual connection in the binding handle
916 $closed = $this->closeConnection();
917 $this->conn = false;
918 } else {
919 $closed = true; // already closed; nothing to do
920 }
921
922 $this->opened = false;
923
924 // Throw any unexpected errors after having disconnected
925 if ( $exception instanceof Exception ) {
926 throw $exception;
927 }
928
929 // Sanity check that no callbacks are dangling
930 if (
931 $this->trxIdleCallbacks || $this->trxPreCommitCallbacks || $this->trxEndCallbacks
932 ) {
933 throw new RuntimeException(
934 "Transaction callbacks are still pending:\n" .
935 implode( ', ', $this->pendingWriteAndCallbackCallers() )
936 );
937 }
938
939 return $closed;
940 }
941
942 /**
943 * Make sure isOpen() returns true as a sanity check
944 *
945 * @throws DBUnexpectedError
946 */
947 protected function assertOpen() {
948 if ( !$this->isOpen() ) {
949 throw new DBUnexpectedError( $this, "DB connection was already closed." );
950 }
951 }
952
953 /**
954 * Closes underlying database connection
955 * @since 1.20
956 * @return bool Whether connection was closed successfully
957 */
958 abstract protected function closeConnection();
959
960 /**
961 * @param string $error Fallback error message, used if none is given by DB
962 * @throws DBConnectionError
963 */
964 public function reportConnectionError( $error = 'Unknown error' ) {
965 $myError = $this->lastError();
966 if ( $myError ) {
967 $error = $myError;
968 }
969
970 # New method
971 throw new DBConnectionError( $this, $error );
972 }
973
974 /**
975 * Run a query and return a DBMS-dependent wrapper (that has all IResultWrapper methods)
976 *
977 * This might return things, such as mysqli_result, that do not formally implement
978 * IResultWrapper, but nonetheless implement all of its methods correctly
979 *
980 * @param string $sql SQL query.
981 * @return IResultWrapper|bool Iterator to feed to fetchObject/fetchRow; false on failure
982 */
983 abstract protected function doQuery( $sql );
984
985 /**
986 * Determine whether a query writes to the DB.
987 * Should return true if unsure.
988 *
989 * @param string $sql
990 * @return bool
991 */
992 protected function isWriteQuery( $sql ) {
993 return !preg_match(
994 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SET|SHOW|EXPLAIN|\(SELECT)\b/i', $sql );
995 }
996
997 /**
998 * @param string $sql
999 * @return string|null
1000 */
1001 protected function getQueryVerb( $sql ) {
1002 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ? strtoupper( $m[1] ) : null;
1003 }
1004
1005 /**
1006 * Determine whether a SQL statement is sensitive to isolation level.
1007 * A SQL statement is considered transactable if its result could vary
1008 * depending on the transaction isolation level. Operational commands
1009 * such as 'SET' and 'SHOW' are not considered to be transactable.
1010 *
1011 * @param string $sql
1012 * @return bool
1013 */
1014 protected function isTransactableQuery( $sql ) {
1015 return !in_array(
1016 $this->getQueryVerb( $sql ),
1017 [ 'BEGIN', 'COMMIT', 'ROLLBACK', 'SHOW', 'SET', 'CREATE', 'ALTER' ],
1018 true
1019 );
1020 }
1021
1022 /**
1023 * @param string $sql A SQL query
1024 * @return bool Whether $sql is SQL for TEMPORARY table operation
1025 */
1026 protected function registerTempTableOperation( $sql ) {
1027 if ( preg_match(
1028 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1029 $sql,
1030 $matches
1031 ) ) {
1032 $this->sessionTempTables[$matches[1]] = 1;
1033
1034 return true;
1035 } elseif ( preg_match(
1036 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1037 $sql,
1038 $matches
1039 ) ) {
1040 $isTemp = isset( $this->sessionTempTables[$matches[1]] );
1041 unset( $this->sessionTempTables[$matches[1]] );
1042
1043 return $isTemp;
1044 } elseif ( preg_match(
1045 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1046 $sql,
1047 $matches
1048 ) ) {
1049 return isset( $this->sessionTempTables[$matches[1]] );
1050 } elseif ( preg_match(
1051 '/^(?:INSERT\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+[`"\']?(\w+)[`"\']?/i',
1052 $sql,
1053 $matches
1054 ) ) {
1055 return isset( $this->sessionTempTables[$matches[1]] );
1056 }
1057
1058 return false;
1059 }
1060
1061 public function query( $sql, $fname = __METHOD__, $tempIgnore = false ) {
1062 $this->assertTransactionStatus( $sql, $fname );
1063
1064 $priorWritesPending = $this->writesOrCallbacksPending();
1065 $this->lastQuery = $sql;
1066
1067 $isWrite = $this->isWriteQuery( $sql );
1068 if ( $isWrite ) {
1069 $isNonTempWrite = !$this->registerTempTableOperation( $sql );
1070 } else {
1071 $isNonTempWrite = false;
1072 }
1073
1074 if ( $isWrite ) {
1075 if ( $this->getLBInfo( 'replica' ) === true ) {
1076 throw new DBError(
1077 $this,
1078 'Write operations are not allowed on replica database connections.'
1079 );
1080 }
1081 # In theory, non-persistent writes are allowed in read-only mode, but due to things
1082 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1083 $reason = $this->getReadOnlyReason();
1084 if ( $reason !== false ) {
1085 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
1086 }
1087 # Set a flag indicating that writes have been done
1088 $this->lastWriteTime = microtime( true );
1089 }
1090
1091 # Add trace comment to the begin of the sql string, right after the operator.
1092 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1093 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1094
1095 # Start implicit transactions that wrap the request if DBO_TRX is enabled
1096 if ( !$this->trxLevel && $this->getFlag( self::DBO_TRX )
1097 && $this->isTransactableQuery( $sql )
1098 ) {
1099 $this->begin( __METHOD__ . " ($fname)", self::TRANSACTION_INTERNAL );
1100 $this->trxAutomatic = true;
1101 }
1102
1103 # Keep track of whether the transaction has write queries pending
1104 if ( $this->trxLevel && !$this->trxDoneWrites && $isWrite ) {
1105 $this->trxDoneWrites = true;
1106 $this->trxProfiler->transactionWritingIn(
1107 $this->server, $this->dbName, $this->trxShortId );
1108 }
1109
1110 if ( $this->getFlag( self::DBO_DEBUG ) ) {
1111 $this->queryLogger->debug( "{$this->dbName} {$commentedSql}" );
1112 }
1113
1114 # Avoid fatals if close() was called
1115 $this->assertOpen();
1116
1117 # Send the query to the server and fetch any corresponding errors
1118 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
1119 $lastError = $this->lastError();
1120 $lastErrno = $this->lastErrno();
1121
1122 # Try reconnecting if the connection was lost
1123 if ( $ret === false && $this->wasConnectionLoss() ) {
1124 # Check if any meaningful session state was lost
1125 $recoverable = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1126 # Update session state tracking and try to restore the connection
1127 $reconnected = $this->replaceLostConnection( __METHOD__ );
1128 # Silently resend the query to the server if it is safe and possible
1129 if ( $reconnected && $recoverable ) {
1130 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
1131 $lastError = $this->lastError();
1132 $lastErrno = $this->lastErrno();
1133
1134 if ( $ret === false && $this->wasConnectionLoss() ) {
1135 # Query probably causes disconnects; reconnect and do not re-run it
1136 $this->replaceLostConnection( __METHOD__ );
1137 }
1138 }
1139 }
1140
1141 if ( $ret === false ) {
1142 if ( $this->trxLevel && !$this->wasKnownStatementRollbackError() ) {
1143 # Either the query was aborted or all queries after BEGIN where aborted.
1144 if ( $this->explicitTrxActive() || $priorWritesPending ) {
1145 # In the first case, the only options going forward are (a) ROLLBACK, or
1146 # (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
1147 # option is ROLLBACK, since the snapshots would have been released.
1148 if ( is_object( $tempIgnore ) ) {
1149 // Ugly hack to know that savepoints are in use for postgres
1150 // FIXME: remove this and make DatabasePostgres use ATOMIC_CANCELABLE
1151 } else {
1152 $this->trxStatus = self::STATUS_TRX_ERROR;
1153 $this->trxStatusCause =
1154 $this->makeQueryException( $lastError, $lastErrno, $sql, $fname );
1155 $tempIgnore = false; // cannot recover
1156 }
1157 } else {
1158 # Nothing prior was there to lose from the transaction
1159 $this->trxStatus = self::STATUS_TRX_OK;
1160 }
1161 }
1162
1163 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $tempIgnore );
1164 }
1165
1166 return $this->resultObject( $ret );
1167 }
1168
1169 /**
1170 * Wrapper for query() that also handles profiling, logging, and affected row count updates
1171 *
1172 * @param string $sql Original SQL query
1173 * @param string $commentedSql SQL query with debugging/trace comment
1174 * @param bool $isWrite Whether the query is a (non-temporary) write operation
1175 * @param string $fname Name of the calling function
1176 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1177 * object for a successful read query, or false on failure
1178 */
1179 private function doProfiledQuery( $sql, $commentedSql, $isWrite, $fname ) {
1180 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1181 # generalizeSQL() will probably cut down the query to reasonable
1182 # logging size most of the time. The substr is really just a sanity check.
1183 if ( $isMaster ) {
1184 $queryProf = 'query-m: ' . substr( self::generalizeSQL( $sql ), 0, 255 );
1185 } else {
1186 $queryProf = 'query: ' . substr( self::generalizeSQL( $sql ), 0, 255 );
1187 }
1188
1189 # Include query transaction state
1190 $queryProf .= $this->trxShortId ? " [TRX#{$this->trxShortId}]" : "";
1191
1192 $startTime = microtime( true );
1193 if ( $this->profiler ) {
1194 call_user_func( [ $this->profiler, 'profileIn' ], $queryProf );
1195 }
1196 $this->affectedRowCount = null;
1197 $ret = $this->doQuery( $commentedSql );
1198 $this->affectedRowCount = $this->affectedRows();
1199 if ( $this->profiler ) {
1200 call_user_func( [ $this->profiler, 'profileOut' ], $queryProf );
1201 }
1202 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1203
1204 unset( $queryProfSection ); // profile out (if set)
1205
1206 if ( $ret !== false ) {
1207 $this->lastPing = $startTime;
1208 if ( $isWrite && $this->trxLevel ) {
1209 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1210 $this->trxWriteCallers[] = $fname;
1211 }
1212 }
1213
1214 if ( $sql === self::PING_QUERY ) {
1215 $this->rttEstimate = $queryRuntime;
1216 }
1217
1218 $this->trxProfiler->recordQueryCompletion(
1219 $queryProf, $startTime, $isWrite, $this->affectedRows()
1220 );
1221 $this->queryLogger->debug( $sql, [
1222 'method' => $fname,
1223 'master' => $isMaster,
1224 'runtime' => $queryRuntime,
1225 ] );
1226
1227 return $ret;
1228 }
1229
1230 /**
1231 * Update the estimated run-time of a query, not counting large row lock times
1232 *
1233 * LoadBalancer can be set to rollback transactions that will create huge replication
1234 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1235 * queries, like inserting a row can take a long time due to row locking. This method
1236 * uses some simple heuristics to discount those cases.
1237 *
1238 * @param string $sql A SQL write query
1239 * @param float $runtime Total runtime, including RTT
1240 * @param int $affected Affected row count
1241 */
1242 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1243 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1244 $indicativeOfReplicaRuntime = true;
1245 if ( $runtime > self::SLOW_WRITE_SEC ) {
1246 $verb = $this->getQueryVerb( $sql );
1247 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1248 if ( $verb === 'INSERT' ) {
1249 $indicativeOfReplicaRuntime = $this->affectedRows() > self::SMALL_WRITE_ROWS;
1250 } elseif ( $verb === 'REPLACE' ) {
1251 $indicativeOfReplicaRuntime = $this->affectedRows() > self::SMALL_WRITE_ROWS / 2;
1252 }
1253 }
1254
1255 $this->trxWriteDuration += $runtime;
1256 $this->trxWriteQueryCount += 1;
1257 $this->trxWriteAffectedRows += $affected;
1258 if ( $indicativeOfReplicaRuntime ) {
1259 $this->trxWriteAdjDuration += $runtime;
1260 $this->trxWriteAdjQueryCount += 1;
1261 }
1262 }
1263
1264 /**
1265 * @param string $sql
1266 * @param string $fname
1267 * @throws DBTransactionStateError
1268 */
1269 private function assertTransactionStatus( $sql, $fname ) {
1270 if (
1271 $this->trxStatus < self::STATUS_TRX_OK &&
1272 $this->getQueryVerb( $sql ) !== 'ROLLBACK' // transaction/savepoint
1273 ) {
1274 throw new DBTransactionStateError(
1275 $this,
1276 "Cannot execute query from $fname while transaction status is ERROR. ",
1277 [],
1278 $this->trxStatusCause
1279 );
1280 }
1281 }
1282
1283 /**
1284 * Determine whether or not it is safe to retry queries after a database
1285 * connection is lost
1286 *
1287 * @param string $sql SQL query
1288 * @param bool $priorWritesPending Whether there is a transaction open with
1289 * possible write queries or transaction pre-commit/idle callbacks
1290 * waiting on it to finish.
1291 * @return bool True if it is safe to retry the query, false otherwise
1292 */
1293 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1294 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1295 # Dropped connections also mean that named locks are automatically released.
1296 # Only allow error suppression in autocommit mode or when the lost transaction
1297 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1298 if ( $this->namedLocksHeld ) {
1299 return false; // possible critical section violation
1300 } elseif ( $this->sessionTempTables ) {
1301 return false; // tables might be queried latter
1302 } elseif ( $sql === 'COMMIT' ) {
1303 return !$priorWritesPending; // nothing written anyway? (T127428)
1304 } elseif ( $sql === 'ROLLBACK' ) {
1305 return true; // transaction lost...which is also what was requested :)
1306 } elseif ( $this->explicitTrxActive() ) {
1307 return false; // don't drop atomocity and explicit snapshots
1308 } elseif ( $priorWritesPending ) {
1309 return false; // prior writes lost from implicit transaction
1310 }
1311
1312 return true;
1313 }
1314
1315 /**
1316 * Clean things up after session (and thus transaction) loss
1317 */
1318 private function handleSessionLoss() {
1319 // Clean up tracking of session-level things...
1320 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1321 // https://www.postgresql.org/docs/9.1/static/sql-createtable.html (ignoring ON COMMIT)
1322 $this->sessionTempTables = [];
1323 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1324 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1325 $this->namedLocksHeld = [];
1326 // Session loss implies transaction loss
1327 $this->handleTransactionLoss();
1328 }
1329
1330 /**
1331 * Clean things up after transaction loss
1332 */
1333 private function handleTransactionLoss() {
1334 $this->trxLevel = 0;
1335 $this->trxAtomicCounter = 0;
1336 $this->trxIdleCallbacks = []; // T67263; transaction already lost
1337 $this->trxPreCommitCallbacks = []; // T67263; transaction already lost
1338 try {
1339 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1340 // If callback suppression is set then the array will remain unhandled.
1341 $this->runOnTransactionIdleCallbacks( self::TRIGGER_ROLLBACK );
1342 } catch ( Exception $ex ) {
1343 // Already logged; move on...
1344 }
1345 try {
1346 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1347 $this->runTransactionListenerCallbacks( self::TRIGGER_ROLLBACK );
1348 } catch ( Exception $ex ) {
1349 // Already logged; move on...
1350 }
1351 }
1352
1353 /**
1354 * Checks whether the cause of the error is detected to be a timeout.
1355 *
1356 * It returns false by default, and not all engines support detecting this yet.
1357 * If this returns false, it will be treated as a generic query error.
1358 *
1359 * @param string $error Error text
1360 * @param int $errno Error number
1361 * @return bool
1362 */
1363 protected function wasQueryTimeout( $error, $errno ) {
1364 return false;
1365 }
1366
1367 /**
1368 * Report a query error. Log the error, and if neither the object ignore
1369 * flag nor the $tempIgnore flag is set, throw a DBQueryError.
1370 *
1371 * @param string $error
1372 * @param int $errno
1373 * @param string $sql
1374 * @param string $fname
1375 * @param bool $tempIgnore
1376 * @throws DBQueryError
1377 */
1378 public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
1379 if ( $tempIgnore ) {
1380 $this->queryLogger->debug( "SQL ERROR (ignored): $error\n" );
1381 } else {
1382 $exception = $this->makeQueryException( $error, $errno, $sql, $fname );
1383
1384 throw $exception;
1385 }
1386 }
1387
1388 /**
1389 * @param string $error
1390 * @param string|int $errno
1391 * @param string $sql
1392 * @param string $fname
1393 * @return DBError
1394 */
1395 private function makeQueryException( $error, $errno, $sql, $fname ) {
1396 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1397 $this->queryLogger->error(
1398 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1399 $this->getLogContext( [
1400 'method' => __METHOD__,
1401 'errno' => $errno,
1402 'error' => $error,
1403 'sql1line' => $sql1line,
1404 'fname' => $fname,
1405 ] )
1406 );
1407 $this->queryLogger->debug( "SQL ERROR: " . $error . "\n" );
1408 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1409 if ( $wasQueryTimeout ) {
1410 $e = new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1411 } else {
1412 $e = new DBQueryError( $this, $error, $errno, $sql, $fname );
1413 }
1414
1415 return $e;
1416 }
1417
1418 public function freeResult( $res ) {
1419 }
1420
1421 public function selectField(
1422 $table, $var, $cond = '', $fname = __METHOD__, $options = [], $join_conds = []
1423 ) {
1424 if ( $var === '*' ) { // sanity
1425 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1426 }
1427
1428 if ( !is_array( $options ) ) {
1429 $options = [ $options ];
1430 }
1431
1432 $options['LIMIT'] = 1;
1433
1434 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1435 if ( $res === false || !$this->numRows( $res ) ) {
1436 return false;
1437 }
1438
1439 $row = $this->fetchRow( $res );
1440
1441 if ( $row !== false ) {
1442 return reset( $row );
1443 } else {
1444 return false;
1445 }
1446 }
1447
1448 public function selectFieldValues(
1449 $table, $var, $cond = '', $fname = __METHOD__, $options = [], $join_conds = []
1450 ) {
1451 if ( $var === '*' ) { // sanity
1452 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1453 } elseif ( !is_string( $var ) ) { // sanity
1454 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1455 }
1456
1457 if ( !is_array( $options ) ) {
1458 $options = [ $options ];
1459 }
1460
1461 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1462 if ( $res === false ) {
1463 return false;
1464 }
1465
1466 $values = [];
1467 foreach ( $res as $row ) {
1468 $values[] = $row->$var;
1469 }
1470
1471 return $values;
1472 }
1473
1474 /**
1475 * Returns an optional USE INDEX clause to go after the table, and a
1476 * string to go at the end of the query.
1477 *
1478 * @param array $options Associative array of options to be turned into
1479 * an SQL query, valid keys are listed in the function.
1480 * @return array
1481 * @see Database::select()
1482 */
1483 protected function makeSelectOptions( $options ) {
1484 $preLimitTail = $postLimitTail = '';
1485 $startOpts = '';
1486
1487 $noKeyOptions = [];
1488
1489 foreach ( $options as $key => $option ) {
1490 if ( is_numeric( $key ) ) {
1491 $noKeyOptions[$option] = true;
1492 }
1493 }
1494
1495 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1496
1497 $preLimitTail .= $this->makeOrderBy( $options );
1498
1499 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1500 $postLimitTail .= ' FOR UPDATE';
1501 }
1502
1503 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1504 $postLimitTail .= ' LOCK IN SHARE MODE';
1505 }
1506
1507 if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
1508 $startOpts .= 'DISTINCT';
1509 }
1510
1511 # Various MySQL extensions
1512 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1513 $startOpts .= ' /*! STRAIGHT_JOIN */';
1514 }
1515
1516 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1517 $startOpts .= ' HIGH_PRIORITY';
1518 }
1519
1520 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1521 $startOpts .= ' SQL_BIG_RESULT';
1522 }
1523
1524 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1525 $startOpts .= ' SQL_BUFFER_RESULT';
1526 }
1527
1528 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1529 $startOpts .= ' SQL_SMALL_RESULT';
1530 }
1531
1532 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1533 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1534 }
1535
1536 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1537 $startOpts .= ' SQL_CACHE';
1538 }
1539
1540 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1541 $startOpts .= ' SQL_NO_CACHE';
1542 }
1543
1544 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1545 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1546 } else {
1547 $useIndex = '';
1548 }
1549 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1550 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1551 } else {
1552 $ignoreIndex = '';
1553 }
1554
1555 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1556 }
1557
1558 /**
1559 * Returns an optional GROUP BY with an optional HAVING
1560 *
1561 * @param array $options Associative array of options
1562 * @return string
1563 * @see Database::select()
1564 * @since 1.21
1565 */
1566 protected function makeGroupByWithHaving( $options ) {
1567 $sql = '';
1568 if ( isset( $options['GROUP BY'] ) ) {
1569 $gb = is_array( $options['GROUP BY'] )
1570 ? implode( ',', $options['GROUP BY'] )
1571 : $options['GROUP BY'];
1572 $sql .= ' GROUP BY ' . $gb;
1573 }
1574 if ( isset( $options['HAVING'] ) ) {
1575 $having = is_array( $options['HAVING'] )
1576 ? $this->makeList( $options['HAVING'], self::LIST_AND )
1577 : $options['HAVING'];
1578 $sql .= ' HAVING ' . $having;
1579 }
1580
1581 return $sql;
1582 }
1583
1584 /**
1585 * Returns an optional ORDER BY
1586 *
1587 * @param array $options Associative array of options
1588 * @return string
1589 * @see Database::select()
1590 * @since 1.21
1591 */
1592 protected function makeOrderBy( $options ) {
1593 if ( isset( $options['ORDER BY'] ) ) {
1594 $ob = is_array( $options['ORDER BY'] )
1595 ? implode( ',', $options['ORDER BY'] )
1596 : $options['ORDER BY'];
1597
1598 return ' ORDER BY ' . $ob;
1599 }
1600
1601 return '';
1602 }
1603
1604 public function select( $table, $vars, $conds = '', $fname = __METHOD__,
1605 $options = [], $join_conds = [] ) {
1606 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1607
1608 return $this->query( $sql, $fname );
1609 }
1610
1611 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__,
1612 $options = [], $join_conds = []
1613 ) {
1614 if ( is_array( $vars ) ) {
1615 $vars = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1616 }
1617
1618 $options = (array)$options;
1619 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1620 ? $options['USE INDEX']
1621 : [];
1622 $ignoreIndexes = (
1623 isset( $options['IGNORE INDEX'] ) &&
1624 is_array( $options['IGNORE INDEX'] )
1625 )
1626 ? $options['IGNORE INDEX']
1627 : [];
1628
1629 if ( is_array( $table ) ) {
1630 $from = ' FROM ' .
1631 $this->tableNamesWithIndexClauseOrJOIN(
1632 $table, $useIndexes, $ignoreIndexes, $join_conds );
1633 } elseif ( $table != '' ) {
1634 $from = ' FROM ' .
1635 $this->tableNamesWithIndexClauseOrJOIN(
1636 [ $table ], $useIndexes, $ignoreIndexes, [] );
1637 } else {
1638 $from = '';
1639 }
1640
1641 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1642 $this->makeSelectOptions( $options );
1643
1644 if ( is_array( $conds ) ) {
1645 $conds = $this->makeList( $conds, self::LIST_AND );
1646 }
1647
1648 if ( $conds === null || $conds === false ) {
1649 $this->queryLogger->warning(
1650 __METHOD__
1651 . ' called from '
1652 . $fname
1653 . ' with incorrect parameters: $conds must be a string or an array'
1654 );
1655 $conds = '';
1656 }
1657
1658 if ( $conds === '' ) {
1659 $sql = "SELECT $startOpts $vars $from $useIndex $ignoreIndex $preLimitTail";
1660 } elseif ( is_string( $conds ) ) {
1661 $sql = "SELECT $startOpts $vars $from $useIndex $ignoreIndex " .
1662 "WHERE $conds $preLimitTail";
1663 } else {
1664 throw new DBUnexpectedError( $this, __METHOD__ . ' called with incorrect parameters' );
1665 }
1666
1667 if ( isset( $options['LIMIT'] ) ) {
1668 $sql = $this->limitResult( $sql, $options['LIMIT'],
1669 isset( $options['OFFSET'] ) ? $options['OFFSET'] : false );
1670 }
1671 $sql = "$sql $postLimitTail";
1672
1673 if ( isset( $options['EXPLAIN'] ) ) {
1674 $sql = 'EXPLAIN ' . $sql;
1675 }
1676
1677 return $sql;
1678 }
1679
1680 public function selectRow( $table, $vars, $conds, $fname = __METHOD__,
1681 $options = [], $join_conds = []
1682 ) {
1683 $options = (array)$options;
1684 $options['LIMIT'] = 1;
1685 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1686
1687 if ( $res === false ) {
1688 return false;
1689 }
1690
1691 if ( !$this->numRows( $res ) ) {
1692 return false;
1693 }
1694
1695 $obj = $this->fetchObject( $res );
1696
1697 return $obj;
1698 }
1699
1700 public function estimateRowCount(
1701 $table, $var = '*', $conds = '', $fname = __METHOD__, $options = [], $join_conds = []
1702 ) {
1703 $conds = $this->normalizeConditions( $conds, $fname );
1704 $column = $this->extractSingleFieldFromList( $var );
1705 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1706 $conds[] = "$column IS NOT NULL";
1707 }
1708
1709 $res = $this->select(
1710 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1711 );
1712 $row = $res ? $this->fetchRow( $res ) : [];
1713
1714 return isset( $row['rowcount'] ) ? (int)$row['rowcount'] : 0;
1715 }
1716
1717 public function selectRowCount(
1718 $tables, $var = '*', $conds = '', $fname = __METHOD__, $options = [], $join_conds = []
1719 ) {
1720 $conds = $this->normalizeConditions( $conds, $fname );
1721 $column = $this->extractSingleFieldFromList( $var );
1722 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1723 $conds[] = "$column IS NOT NULL";
1724 }
1725
1726 $res = $this->select(
1727 [
1728 'tmp_count' => $this->buildSelectSubquery(
1729 $tables,
1730 '1',
1731 $conds,
1732 $fname,
1733 $options,
1734 $join_conds
1735 )
1736 ],
1737 [ 'rowcount' => 'COUNT(*)' ],
1738 [],
1739 $fname
1740 );
1741 $row = $res ? $this->fetchRow( $res ) : [];
1742
1743 return isset( $row['rowcount'] ) ? (int)$row['rowcount'] : 0;
1744 }
1745
1746 /**
1747 * @param array|string $conds
1748 * @param string $fname
1749 * @return array
1750 */
1751 final protected function normalizeConditions( $conds, $fname ) {
1752 if ( $conds === null || $conds === false ) {
1753 $this->queryLogger->warning(
1754 __METHOD__
1755 . ' called from '
1756 . $fname
1757 . ' with incorrect parameters: $conds must be a string or an array'
1758 );
1759 $conds = '';
1760 }
1761
1762 if ( !is_array( $conds ) ) {
1763 $conds = ( $conds === '' ) ? [] : [ $conds ];
1764 }
1765
1766 return $conds;
1767 }
1768
1769 /**
1770 * @param array|string $var Field parameter in the style of select()
1771 * @return string|null Column name or null; ignores aliases
1772 * @throws DBUnexpectedError Errors out if multiple columns are given
1773 */
1774 final protected function extractSingleFieldFromList( $var ) {
1775 if ( is_array( $var ) ) {
1776 if ( !$var ) {
1777 $column = null;
1778 } elseif ( count( $var ) == 1 ) {
1779 $column = isset( $var[0] ) ? $var[0] : reset( $var );
1780 } else {
1781 throw new DBUnexpectedError( $this, __METHOD__ . ': got multiple columns.' );
1782 }
1783 } else {
1784 $column = $var;
1785 }
1786
1787 return $column;
1788 }
1789
1790 /**
1791 * Removes most variables from an SQL query and replaces them with X or N for numbers.
1792 * It's only slightly flawed. Don't use for anything important.
1793 *
1794 * @param string $sql A SQL Query
1795 *
1796 * @return string
1797 */
1798 protected static function generalizeSQL( $sql ) {
1799 # This does the same as the regexp below would do, but in such a way
1800 # as to avoid crashing php on some large strings.
1801 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
1802
1803 $sql = str_replace( "\\\\", '', $sql );
1804 $sql = str_replace( "\\'", '', $sql );
1805 $sql = str_replace( "\\\"", '', $sql );
1806 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
1807 $sql = preg_replace( '/".*"/s', "'X'", $sql );
1808
1809 # All newlines, tabs, etc replaced by single space
1810 $sql = preg_replace( '/\s+/', ' ', $sql );
1811
1812 # All numbers => N,
1813 # except the ones surrounded by characters, e.g. l10n
1814 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
1815 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
1816
1817 return $sql;
1818 }
1819
1820 public function fieldExists( $table, $field, $fname = __METHOD__ ) {
1821 $info = $this->fieldInfo( $table, $field );
1822
1823 return (bool)$info;
1824 }
1825
1826 public function indexExists( $table, $index, $fname = __METHOD__ ) {
1827 if ( !$this->tableExists( $table ) ) {
1828 return null;
1829 }
1830
1831 $info = $this->indexInfo( $table, $index, $fname );
1832 if ( is_null( $info ) ) {
1833 return null;
1834 } else {
1835 return $info !== false;
1836 }
1837 }
1838
1839 public function tableExists( $table, $fname = __METHOD__ ) {
1840 $tableRaw = $this->tableName( $table, 'raw' );
1841 if ( isset( $this->sessionTempTables[$tableRaw] ) ) {
1842 return true; // already known to exist
1843 }
1844
1845 $table = $this->tableName( $table );
1846 $ignoreErrors = true;
1847 $res = $this->query( "SELECT 1 FROM $table LIMIT 1", $fname, $ignoreErrors );
1848
1849 return (bool)$res;
1850 }
1851
1852 public function indexUnique( $table, $index ) {
1853 $indexInfo = $this->indexInfo( $table, $index );
1854
1855 if ( !$indexInfo ) {
1856 return null;
1857 }
1858
1859 return !$indexInfo[0]->Non_unique;
1860 }
1861
1862 /**
1863 * Helper for Database::insert().
1864 *
1865 * @param array $options
1866 * @return string
1867 */
1868 protected function makeInsertOptions( $options ) {
1869 return implode( ' ', $options );
1870 }
1871
1872 public function insert( $table, $a, $fname = __METHOD__, $options = [] ) {
1873 # No rows to insert, easy just return now
1874 if ( !count( $a ) ) {
1875 return true;
1876 }
1877
1878 $table = $this->tableName( $table );
1879
1880 if ( !is_array( $options ) ) {
1881 $options = [ $options ];
1882 }
1883
1884 $fh = null;
1885 if ( isset( $options['fileHandle'] ) ) {
1886 $fh = $options['fileHandle'];
1887 }
1888 $options = $this->makeInsertOptions( $options );
1889
1890 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1891 $multi = true;
1892 $keys = array_keys( $a[0] );
1893 } else {
1894 $multi = false;
1895 $keys = array_keys( $a );
1896 }
1897
1898 $sql = 'INSERT ' . $options .
1899 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1900
1901 if ( $multi ) {
1902 $first = true;
1903 foreach ( $a as $row ) {
1904 if ( $first ) {
1905 $first = false;
1906 } else {
1907 $sql .= ',';
1908 }
1909 $sql .= '(' . $this->makeList( $row ) . ')';
1910 }
1911 } else {
1912 $sql .= '(' . $this->makeList( $a ) . ')';
1913 }
1914
1915 if ( $fh !== null && false === fwrite( $fh, $sql ) ) {
1916 return false;
1917 } elseif ( $fh !== null ) {
1918 return true;
1919 }
1920
1921 return (bool)$this->query( $sql, $fname );
1922 }
1923
1924 /**
1925 * Make UPDATE options array for Database::makeUpdateOptions
1926 *
1927 * @param array $options
1928 * @return array
1929 */
1930 protected function makeUpdateOptionsArray( $options ) {
1931 if ( !is_array( $options ) ) {
1932 $options = [ $options ];
1933 }
1934
1935 $opts = [];
1936
1937 if ( in_array( 'IGNORE', $options ) ) {
1938 $opts[] = 'IGNORE';
1939 }
1940
1941 return $opts;
1942 }
1943
1944 /**
1945 * Make UPDATE options for the Database::update function
1946 *
1947 * @param array $options The options passed to Database::update
1948 * @return string
1949 */
1950 protected function makeUpdateOptions( $options ) {
1951 $opts = $this->makeUpdateOptionsArray( $options );
1952
1953 return implode( ' ', $opts );
1954 }
1955
1956 public function update( $table, $values, $conds, $fname = __METHOD__, $options = [] ) {
1957 $table = $this->tableName( $table );
1958 $opts = $this->makeUpdateOptions( $options );
1959 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self::LIST_SET );
1960
1961 if ( $conds !== [] && $conds !== '*' ) {
1962 $sql .= " WHERE " . $this->makeList( $conds, self::LIST_AND );
1963 }
1964
1965 return (bool)$this->query( $sql, $fname );
1966 }
1967
1968 public function makeList( $a, $mode = self::LIST_COMMA ) {
1969 if ( !is_array( $a ) ) {
1970 throw new DBUnexpectedError( $this, __METHOD__ . ' called with incorrect parameters' );
1971 }
1972
1973 $first = true;
1974 $list = '';
1975
1976 foreach ( $a as $field => $value ) {
1977 if ( !$first ) {
1978 if ( $mode == self::LIST_AND ) {
1979 $list .= ' AND ';
1980 } elseif ( $mode == self::LIST_OR ) {
1981 $list .= ' OR ';
1982 } else {
1983 $list .= ',';
1984 }
1985 } else {
1986 $first = false;
1987 }
1988
1989 if ( ( $mode == self::LIST_AND || $mode == self::LIST_OR ) && is_numeric( $field ) ) {
1990 $list .= "($value)";
1991 } elseif ( $mode == self::LIST_SET && is_numeric( $field ) ) {
1992 $list .= "$value";
1993 } elseif (
1994 ( $mode == self::LIST_AND || $mode == self::LIST_OR ) && is_array( $value )
1995 ) {
1996 // Remove null from array to be handled separately if found
1997 $includeNull = false;
1998 foreach ( array_keys( $value, null, true ) as $nullKey ) {
1999 $includeNull = true;
2000 unset( $value[$nullKey] );
2001 }
2002 if ( count( $value ) == 0 && !$includeNull ) {
2003 throw new InvalidArgumentException(
2004 __METHOD__ . ": empty input for field $field" );
2005 } elseif ( count( $value ) == 0 ) {
2006 // only check if $field is null
2007 $list .= "$field IS NULL";
2008 } else {
2009 // IN clause contains at least one valid element
2010 if ( $includeNull ) {
2011 // Group subconditions to ensure correct precedence
2012 $list .= '(';
2013 }
2014 if ( count( $value ) == 1 ) {
2015 // Special-case single values, as IN isn't terribly efficient
2016 // Don't necessarily assume the single key is 0; we don't
2017 // enforce linear numeric ordering on other arrays here.
2018 $value = array_values( $value )[0];
2019 $list .= $field . " = " . $this->addQuotes( $value );
2020 } else {
2021 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
2022 }
2023 // if null present in array, append IS NULL
2024 if ( $includeNull ) {
2025 $list .= " OR $field IS NULL)";
2026 }
2027 }
2028 } elseif ( $value === null ) {
2029 if ( $mode == self::LIST_AND || $mode == self::LIST_OR ) {
2030 $list .= "$field IS ";
2031 } elseif ( $mode == self::LIST_SET ) {
2032 $list .= "$field = ";
2033 }
2034 $list .= 'NULL';
2035 } else {
2036 if (
2037 $mode == self::LIST_AND || $mode == self::LIST_OR || $mode == self::LIST_SET
2038 ) {
2039 $list .= "$field = ";
2040 }
2041 $list .= $mode == self::LIST_NAMES ? $value : $this->addQuotes( $value );
2042 }
2043 }
2044
2045 return $list;
2046 }
2047
2048 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
2049 $conds = [];
2050
2051 foreach ( $data as $base => $sub ) {
2052 if ( count( $sub ) ) {
2053 $conds[] = $this->makeList(
2054 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
2055 self::LIST_AND );
2056 }
2057 }
2058
2059 if ( $conds ) {
2060 return $this->makeList( $conds, self::LIST_OR );
2061 } else {
2062 // Nothing to search for...
2063 return false;
2064 }
2065 }
2066
2067 public function aggregateValue( $valuedata, $valuename = 'value' ) {
2068 return $valuename;
2069 }
2070
2071 public function bitNot( $field ) {
2072 return "(~$field)";
2073 }
2074
2075 public function bitAnd( $fieldLeft, $fieldRight ) {
2076 return "($fieldLeft & $fieldRight)";
2077 }
2078
2079 public function bitOr( $fieldLeft, $fieldRight ) {
2080 return "($fieldLeft | $fieldRight)";
2081 }
2082
2083 public function buildConcat( $stringList ) {
2084 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2085 }
2086
2087 public function buildGroupConcatField(
2088 $delim, $table, $field, $conds = '', $join_conds = []
2089 ) {
2090 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
2091
2092 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2093 }
2094
2095 public function buildSubstring( $input, $startPosition, $length = null ) {
2096 $this->assertBuildSubstringParams( $startPosition, $length );
2097 $functionBody = "$input FROM $startPosition";
2098 if ( $length !== null ) {
2099 $functionBody .= " FOR $length";
2100 }
2101 return 'SUBSTRING(' . $functionBody . ')';
2102 }
2103
2104 /**
2105 * Check type and bounds for parameters to self::buildSubstring()
2106 *
2107 * All supported databases have substring functions that behave the same for
2108 * positive $startPosition and non-negative $length, but behaviors differ when
2109 * given 0 or negative $startPosition or negative $length. The simplest
2110 * solution to that is to just forbid those values.
2111 *
2112 * @param int $startPosition
2113 * @param int|null $length
2114 * @since 1.31
2115 */
2116 protected function assertBuildSubstringParams( $startPosition, $length ) {
2117 if ( !is_int( $startPosition ) || $startPosition <= 0 ) {
2118 throw new InvalidArgumentException(
2119 '$startPosition must be a positive integer'
2120 );
2121 }
2122 if ( !( is_int( $length ) && $length >= 0 || $length === null ) ) {
2123 throw new InvalidArgumentException(
2124 '$length must be null or an integer greater than or equal to 0'
2125 );
2126 }
2127 }
2128
2129 public function buildStringCast( $field ) {
2130 return $field;
2131 }
2132
2133 public function buildIntegerCast( $field ) {
2134 return 'CAST( ' . $field . ' AS INTEGER )';
2135 }
2136
2137 public function buildSelectSubquery(
2138 $table, $vars, $conds = '', $fname = __METHOD__,
2139 $options = [], $join_conds = []
2140 ) {
2141 return new Subquery(
2142 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2143 );
2144 }
2145
2146 public function databasesAreIndependent() {
2147 return false;
2148 }
2149
2150 public function selectDB( $db ) {
2151 # Stub. Shouldn't cause serious problems if it's not overridden, but
2152 # if your database engine supports a concept similar to MySQL's
2153 # databases you may as well.
2154 $this->dbName = $db;
2155
2156 return true;
2157 }
2158
2159 public function getDBname() {
2160 return $this->dbName;
2161 }
2162
2163 public function getServer() {
2164 return $this->server;
2165 }
2166
2167 public function tableName( $name, $format = 'quoted' ) {
2168 if ( $name instanceof Subquery ) {
2169 throw new DBUnexpectedError(
2170 $this,
2171 __METHOD__ . ': got Subquery instance when expecting a string.'
2172 );
2173 }
2174
2175 # Skip the entire process when we have a string quoted on both ends.
2176 # Note that we check the end so that we will still quote any use of
2177 # use of `database`.table. But won't break things if someone wants
2178 # to query a database table with a dot in the name.
2179 if ( $this->isQuotedIdentifier( $name ) ) {
2180 return $name;
2181 }
2182
2183 # Lets test for any bits of text that should never show up in a table
2184 # name. Basically anything like JOIN or ON which are actually part of
2185 # SQL queries, but may end up inside of the table value to combine
2186 # sql. Such as how the API is doing.
2187 # Note that we use a whitespace test rather than a \b test to avoid
2188 # any remote case where a word like on may be inside of a table name
2189 # surrounded by symbols which may be considered word breaks.
2190 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2191 $this->queryLogger->warning(
2192 __METHOD__ . ": use of subqueries is not supported this way.",
2193 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2194 );
2195
2196 return $name;
2197 }
2198
2199 # Split database and table into proper variables.
2200 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2201
2202 # Quote $table and apply the prefix if not quoted.
2203 # $tableName might be empty if this is called from Database::replaceVars()
2204 $tableName = "{$prefix}{$table}";
2205 if ( $format === 'quoted'
2206 && !$this->isQuotedIdentifier( $tableName )
2207 && $tableName !== ''
2208 ) {
2209 $tableName = $this->addIdentifierQuotes( $tableName );
2210 }
2211
2212 # Quote $schema and $database and merge them with the table name if needed
2213 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2214 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2215
2216 return $tableName;
2217 }
2218
2219 /**
2220 * Get the table components needed for a query given the currently selected database
2221 *
2222 * @param string $name Table name in the form of db.schema.table, db.table, or table
2223 * @return array (DB name or "" for default, schema name, table prefix, table name)
2224 */
2225 protected function qualifiedTableComponents( $name ) {
2226 # We reverse the explode so that database.table and table both output the correct table.
2227 $dbDetails = explode( '.', $name, 3 );
2228 if ( count( $dbDetails ) == 3 ) {
2229 list( $database, $schema, $table ) = $dbDetails;
2230 # We don't want any prefix added in this case
2231 $prefix = '';
2232 } elseif ( count( $dbDetails ) == 2 ) {
2233 list( $database, $table ) = $dbDetails;
2234 # We don't want any prefix added in this case
2235 $prefix = '';
2236 # In dbs that support it, $database may actually be the schema
2237 # but that doesn't affect any of the functionality here
2238 $schema = '';
2239 } else {
2240 list( $table ) = $dbDetails;
2241 if ( isset( $this->tableAliases[$table] ) ) {
2242 $database = $this->tableAliases[$table]['dbname'];
2243 $schema = is_string( $this->tableAliases[$table]['schema'] )
2244 ? $this->tableAliases[$table]['schema']
2245 : $this->schema;
2246 $prefix = is_string( $this->tableAliases[$table]['prefix'] )
2247 ? $this->tableAliases[$table]['prefix']
2248 : $this->tablePrefix;
2249 } else {
2250 $database = '';
2251 $schema = $this->schema; # Default schema
2252 $prefix = $this->tablePrefix; # Default prefix
2253 }
2254 }
2255
2256 return [ $database, $schema, $prefix, $table ];
2257 }
2258
2259 /**
2260 * @param string|null $namespace Database or schema
2261 * @param string $relation Name of table, view, sequence, etc...
2262 * @param string $format One of (raw, quoted)
2263 * @return string Relation name with quoted and merged $namespace as needed
2264 */
2265 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2266 if ( strlen( $namespace ) ) {
2267 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2268 $namespace = $this->addIdentifierQuotes( $namespace );
2269 }
2270 $relation = $namespace . '.' . $relation;
2271 }
2272
2273 return $relation;
2274 }
2275
2276 public function tableNames() {
2277 $inArray = func_get_args();
2278 $retVal = [];
2279
2280 foreach ( $inArray as $name ) {
2281 $retVal[$name] = $this->tableName( $name );
2282 }
2283
2284 return $retVal;
2285 }
2286
2287 public function tableNamesN() {
2288 $inArray = func_get_args();
2289 $retVal = [];
2290
2291 foreach ( $inArray as $name ) {
2292 $retVal[] = $this->tableName( $name );
2293 }
2294
2295 return $retVal;
2296 }
2297
2298 /**
2299 * Get an aliased table name
2300 *
2301 * This returns strings like "tableName AS newTableName" for aliased tables
2302 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2303 *
2304 * @see Database::tableName()
2305 * @param string|Subquery $table Table name or object with a 'sql' field
2306 * @param string|bool $alias Table alias (optional)
2307 * @return string SQL name for aliased table. Will not alias a table to its own name
2308 */
2309 protected function tableNameWithAlias( $table, $alias = false ) {
2310 if ( is_string( $table ) ) {
2311 $quotedTable = $this->tableName( $table );
2312 } elseif ( $table instanceof Subquery ) {
2313 $quotedTable = (string)$table;
2314 } else {
2315 throw new InvalidArgumentException( "Table must be a string or Subquery." );
2316 }
2317
2318 if ( !strlen( $alias ) || $alias === $table ) {
2319 if ( $table instanceof Subquery ) {
2320 throw new InvalidArgumentException( "Subquery table missing alias." );
2321 }
2322
2323 return $quotedTable;
2324 } else {
2325 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2326 }
2327 }
2328
2329 /**
2330 * Gets an array of aliased table names
2331 *
2332 * @param array $tables [ [alias] => table ]
2333 * @return string[] See tableNameWithAlias()
2334 */
2335 protected function tableNamesWithAlias( $tables ) {
2336 $retval = [];
2337 foreach ( $tables as $alias => $table ) {
2338 if ( is_numeric( $alias ) ) {
2339 $alias = $table;
2340 }
2341 $retval[] = $this->tableNameWithAlias( $table, $alias );
2342 }
2343
2344 return $retval;
2345 }
2346
2347 /**
2348 * Get an aliased field name
2349 * e.g. fieldName AS newFieldName
2350 *
2351 * @param string $name Field name
2352 * @param string|bool $alias Alias (optional)
2353 * @return string SQL name for aliased field. Will not alias a field to its own name
2354 */
2355 protected function fieldNameWithAlias( $name, $alias = false ) {
2356 if ( !$alias || (string)$alias === (string)$name ) {
2357 return $name;
2358 } else {
2359 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2360 }
2361 }
2362
2363 /**
2364 * Gets an array of aliased field names
2365 *
2366 * @param array $fields [ [alias] => field ]
2367 * @return string[] See fieldNameWithAlias()
2368 */
2369 protected function fieldNamesWithAlias( $fields ) {
2370 $retval = [];
2371 foreach ( $fields as $alias => $field ) {
2372 if ( is_numeric( $alias ) ) {
2373 $alias = $field;
2374 }
2375 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2376 }
2377
2378 return $retval;
2379 }
2380
2381 /**
2382 * Get the aliased table name clause for a FROM clause
2383 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2384 *
2385 * @param array $tables ( [alias] => table )
2386 * @param array $use_index Same as for select()
2387 * @param array $ignore_index Same as for select()
2388 * @param array $join_conds Same as for select()
2389 * @return string
2390 */
2391 protected function tableNamesWithIndexClauseOrJOIN(
2392 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2393 ) {
2394 $ret = [];
2395 $retJOIN = [];
2396 $use_index = (array)$use_index;
2397 $ignore_index = (array)$ignore_index;
2398 $join_conds = (array)$join_conds;
2399
2400 foreach ( $tables as $alias => $table ) {
2401 if ( !is_string( $alias ) ) {
2402 // No alias? Set it equal to the table name
2403 $alias = $table;
2404 }
2405
2406 if ( is_array( $table ) ) {
2407 // A parenthesized group
2408 if ( count( $table ) > 1 ) {
2409 $joinedTable = '(' .
2410 $this->tableNamesWithIndexClauseOrJOIN(
2411 $table, $use_index, $ignore_index, $join_conds ) . ')';
2412 } else {
2413 // Degenerate case
2414 $innerTable = reset( $table );
2415 $innerAlias = key( $table );
2416 $joinedTable = $this->tableNameWithAlias(
2417 $innerTable,
2418 is_string( $innerAlias ) ? $innerAlias : $innerTable
2419 );
2420 }
2421 } else {
2422 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2423 }
2424
2425 // Is there a JOIN clause for this table?
2426 if ( isset( $join_conds[$alias] ) ) {
2427 list( $joinType, $conds ) = $join_conds[$alias];
2428 $tableClause = $joinType;
2429 $tableClause .= ' ' . $joinedTable;
2430 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2431 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2432 if ( $use != '' ) {
2433 $tableClause .= ' ' . $use;
2434 }
2435 }
2436 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2437 $ignore = $this->ignoreIndexClause(
2438 implode( ',', (array)$ignore_index[$alias] ) );
2439 if ( $ignore != '' ) {
2440 $tableClause .= ' ' . $ignore;
2441 }
2442 }
2443 $on = $this->makeList( (array)$conds, self::LIST_AND );
2444 if ( $on != '' ) {
2445 $tableClause .= ' ON (' . $on . ')';
2446 }
2447
2448 $retJOIN[] = $tableClause;
2449 } elseif ( isset( $use_index[$alias] ) ) {
2450 // Is there an INDEX clause for this table?
2451 $tableClause = $joinedTable;
2452 $tableClause .= ' ' . $this->useIndexClause(
2453 implode( ',', (array)$use_index[$alias] )
2454 );
2455
2456 $ret[] = $tableClause;
2457 } elseif ( isset( $ignore_index[$alias] ) ) {
2458 // Is there an INDEX clause for this table?
2459 $tableClause = $joinedTable;
2460 $tableClause .= ' ' . $this->ignoreIndexClause(
2461 implode( ',', (array)$ignore_index[$alias] )
2462 );
2463
2464 $ret[] = $tableClause;
2465 } else {
2466 $tableClause = $joinedTable;
2467
2468 $ret[] = $tableClause;
2469 }
2470 }
2471
2472 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2473 $implicitJoins = $ret ? implode( ',', $ret ) : "";
2474 $explicitJoins = $retJOIN ? implode( ' ', $retJOIN ) : "";
2475
2476 // Compile our final table clause
2477 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2478 }
2479
2480 /**
2481 * Allows for index remapping in queries where this is not consistent across DBMS
2482 *
2483 * @param string $index
2484 * @return string
2485 */
2486 protected function indexName( $index ) {
2487 return isset( $this->indexAliases[$index] )
2488 ? $this->indexAliases[$index]
2489 : $index;
2490 }
2491
2492 public function addQuotes( $s ) {
2493 if ( $s instanceof Blob ) {
2494 $s = $s->fetch();
2495 }
2496 if ( $s === null ) {
2497 return 'NULL';
2498 } elseif ( is_bool( $s ) ) {
2499 return (int)$s;
2500 } else {
2501 # This will also quote numeric values. This should be harmless,
2502 # and protects against weird problems that occur when they really
2503 # _are_ strings such as article titles and string->number->string
2504 # conversion is not 1:1.
2505 return "'" . $this->strencode( $s ) . "'";
2506 }
2507 }
2508
2509 /**
2510 * Quotes an identifier using `backticks` or "double quotes" depending on the database type.
2511 * MySQL uses `backticks` while basically everything else uses double quotes.
2512 * Since MySQL is the odd one out here the double quotes are our generic
2513 * and we implement backticks in DatabaseMysqlBase.
2514 *
2515 * @param string $s
2516 * @return string
2517 */
2518 public function addIdentifierQuotes( $s ) {
2519 return '"' . str_replace( '"', '""', $s ) . '"';
2520 }
2521
2522 /**
2523 * Returns if the given identifier looks quoted or not according to
2524 * the database convention for quoting identifiers .
2525 *
2526 * @note Do not use this to determine if untrusted input is safe.
2527 * A malicious user can trick this function.
2528 * @param string $name
2529 * @return bool
2530 */
2531 public function isQuotedIdentifier( $name ) {
2532 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2533 }
2534
2535 /**
2536 * @param string $s
2537 * @param string $escapeChar
2538 * @return string
2539 */
2540 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2541 return str_replace( [ $escapeChar, '%', '_' ],
2542 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2543 $s );
2544 }
2545
2546 public function buildLike() {
2547 $params = func_get_args();
2548
2549 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2550 $params = $params[0];
2551 }
2552
2553 $s = '';
2554
2555 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2556 // may escape backslashes, creating problems of double escaping. The `
2557 // character has good cross-DBMS compatibility, avoiding special operators
2558 // in MS SQL like ^ and %
2559 $escapeChar = '`';
2560
2561 foreach ( $params as $value ) {
2562 if ( $value instanceof LikeMatch ) {
2563 $s .= $value->toString();
2564 } else {
2565 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2566 }
2567 }
2568
2569 return ' LIKE ' .
2570 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2571 }
2572
2573 public function anyChar() {
2574 return new LikeMatch( '_' );
2575 }
2576
2577 public function anyString() {
2578 return new LikeMatch( '%' );
2579 }
2580
2581 public function nextSequenceValue( $seqName ) {
2582 return null;
2583 }
2584
2585 /**
2586 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2587 * is only needed because a) MySQL must be as efficient as possible due to
2588 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2589 * which index to pick. Anyway, other databases might have different
2590 * indexes on a given table. So don't bother overriding this unless you're
2591 * MySQL.
2592 * @param string $index
2593 * @return string
2594 */
2595 public function useIndexClause( $index ) {
2596 return '';
2597 }
2598
2599 /**
2600 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2601 * is only needed because a) MySQL must be as efficient as possible due to
2602 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2603 * which index to pick. Anyway, other databases might have different
2604 * indexes on a given table. So don't bother overriding this unless you're
2605 * MySQL.
2606 * @param string $index
2607 * @return string
2608 */
2609 public function ignoreIndexClause( $index ) {
2610 return '';
2611 }
2612
2613 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
2614 if ( count( $rows ) == 0 ) {
2615 return;
2616 }
2617
2618 // Single row case
2619 if ( !is_array( reset( $rows ) ) ) {
2620 $rows = [ $rows ];
2621 }
2622
2623 try {
2624 $this->startAtomic( $fname, self::ATOMIC_CANCELABLE );
2625 $affectedRowCount = 0;
2626 foreach ( $rows as $row ) {
2627 // Delete rows which collide with this one
2628 $indexWhereClauses = [];
2629 foreach ( $uniqueIndexes as $index ) {
2630 $indexColumns = (array)$index;
2631 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2632 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2633 throw new DBUnexpectedError(
2634 $this,
2635 'New record does not provide all values for unique key (' .
2636 implode( ', ', $indexColumns ) . ')'
2637 );
2638 } elseif ( in_array( null, $indexRowValues, true ) ) {
2639 throw new DBUnexpectedError(
2640 $this,
2641 'New record has a null value for unique key (' .
2642 implode( ', ', $indexColumns ) . ')'
2643 );
2644 }
2645 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND );
2646 }
2647
2648 if ( $indexWhereClauses ) {
2649 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR ), $fname );
2650 $affectedRowCount += $this->affectedRows();
2651 }
2652
2653 // Now insert the row
2654 $this->insert( $table, $row, $fname );
2655 $affectedRowCount += $this->affectedRows();
2656 }
2657 $this->endAtomic( $fname );
2658 $this->affectedRowCount = $affectedRowCount;
2659 } catch ( Exception $e ) {
2660 $this->cancelAtomic( $fname );
2661 throw $e;
2662 }
2663 }
2664
2665 /**
2666 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2667 * statement.
2668 *
2669 * @param string $table Table name
2670 * @param array|string $rows Row(s) to insert
2671 * @param string $fname Caller function name
2672 *
2673 * @return ResultWrapper
2674 */
2675 protected function nativeReplace( $table, $rows, $fname ) {
2676 $table = $this->tableName( $table );
2677
2678 # Single row case
2679 if ( !is_array( reset( $rows ) ) ) {
2680 $rows = [ $rows ];
2681 }
2682
2683 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2684 $first = true;
2685
2686 foreach ( $rows as $row ) {
2687 if ( $first ) {
2688 $first = false;
2689 } else {
2690 $sql .= ',';
2691 }
2692
2693 $sql .= '(' . $this->makeList( $row ) . ')';
2694 }
2695
2696 return $this->query( $sql, $fname );
2697 }
2698
2699 public function upsert( $table, array $rows, array $uniqueIndexes, array $set,
2700 $fname = __METHOD__
2701 ) {
2702 if ( !count( $rows ) ) {
2703 return true; // nothing to do
2704 }
2705
2706 if ( !is_array( reset( $rows ) ) ) {
2707 $rows = [ $rows ];
2708 }
2709
2710 if ( count( $uniqueIndexes ) ) {
2711 $clauses = []; // list WHERE clauses that each identify a single row
2712 foreach ( $rows as $row ) {
2713 foreach ( $uniqueIndexes as $index ) {
2714 $index = is_array( $index ) ? $index : [ $index ]; // columns
2715 $rowKey = []; // unique key to this row
2716 foreach ( $index as $column ) {
2717 $rowKey[$column] = $row[$column];
2718 }
2719 $clauses[] = $this->makeList( $rowKey, self::LIST_AND );
2720 }
2721 }
2722 $where = [ $this->makeList( $clauses, self::LIST_OR ) ];
2723 } else {
2724 $where = false;
2725 }
2726
2727 $affectedRowCount = 0;
2728 try {
2729 $this->startAtomic( $fname, self::ATOMIC_CANCELABLE );
2730 # Update any existing conflicting row(s)
2731 if ( $where !== false ) {
2732 $ok = $this->update( $table, $set, $where, $fname );
2733 $affectedRowCount += $this->affectedRows();
2734 } else {
2735 $ok = true;
2736 }
2737 # Now insert any non-conflicting row(s)
2738 $ok = $this->insert( $table, $rows, $fname, [ 'IGNORE' ] ) && $ok;
2739 $affectedRowCount += $this->affectedRows();
2740 $this->endAtomic( $fname );
2741 $this->affectedRowCount = $affectedRowCount;
2742 } catch ( Exception $e ) {
2743 $this->cancelAtomic( $fname );
2744 throw $e;
2745 }
2746
2747 return $ok;
2748 }
2749
2750 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2751 $fname = __METHOD__
2752 ) {
2753 if ( !$conds ) {
2754 throw new DBUnexpectedError( $this, __METHOD__ . ' called with empty $conds' );
2755 }
2756
2757 $delTable = $this->tableName( $delTable );
2758 $joinTable = $this->tableName( $joinTable );
2759 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2760 if ( $conds != '*' ) {
2761 $sql .= 'WHERE ' . $this->makeList( $conds, self::LIST_AND );
2762 }
2763 $sql .= ')';
2764
2765 $this->query( $sql, $fname );
2766 }
2767
2768 public function textFieldSize( $table, $field ) {
2769 $table = $this->tableName( $table );
2770 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
2771 $res = $this->query( $sql, __METHOD__ );
2772 $row = $this->fetchObject( $res );
2773
2774 $m = [];
2775
2776 if ( preg_match( '/\((.*)\)/', $row->Type, $m ) ) {
2777 $size = $m[1];
2778 } else {
2779 $size = -1;
2780 }
2781
2782 return $size;
2783 }
2784
2785 public function delete( $table, $conds, $fname = __METHOD__ ) {
2786 if ( !$conds ) {
2787 throw new DBUnexpectedError( $this, __METHOD__ . ' called with no conditions' );
2788 }
2789
2790 $table = $this->tableName( $table );
2791 $sql = "DELETE FROM $table";
2792
2793 if ( $conds != '*' ) {
2794 if ( is_array( $conds ) ) {
2795 $conds = $this->makeList( $conds, self::LIST_AND );
2796 }
2797 $sql .= ' WHERE ' . $conds;
2798 }
2799
2800 return $this->query( $sql, $fname );
2801 }
2802
2803 final public function insertSelect(
2804 $destTable, $srcTable, $varMap, $conds,
2805 $fname = __METHOD__, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2806 ) {
2807 static $hints = [ 'NO_AUTO_COLUMNS' ];
2808
2809 $insertOptions = (array)$insertOptions;
2810 $selectOptions = (array)$selectOptions;
2811
2812 if ( $this->cliMode && $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
2813 // For massive migrations with downtime, we don't want to select everything
2814 // into memory and OOM, so do all this native on the server side if possible.
2815 return $this->nativeInsertSelect(
2816 $destTable,
2817 $srcTable,
2818 $varMap,
2819 $conds,
2820 $fname,
2821 array_diff( $insertOptions, $hints ),
2822 $selectOptions,
2823 $selectJoinConds
2824 );
2825 }
2826
2827 return $this->nonNativeInsertSelect(
2828 $destTable,
2829 $srcTable,
2830 $varMap,
2831 $conds,
2832 $fname,
2833 array_diff( $insertOptions, $hints ),
2834 $selectOptions,
2835 $selectJoinConds
2836 );
2837 }
2838
2839 /**
2840 * @param array $insertOptions INSERT options
2841 * @param array $selectOptions SELECT options
2842 * @return bool Whether an INSERT SELECT with these options will be replication safe
2843 * @since 1.31
2844 */
2845 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
2846 return true;
2847 }
2848
2849 /**
2850 * Implementation of insertSelect() based on select() and insert()
2851 *
2852 * @see IDatabase::insertSelect()
2853 * @since 1.30
2854 * @param string $destTable
2855 * @param string|array $srcTable
2856 * @param array $varMap
2857 * @param array $conds
2858 * @param string $fname
2859 * @param array $insertOptions
2860 * @param array $selectOptions
2861 * @param array $selectJoinConds
2862 * @return bool
2863 */
2864 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
2865 $fname = __METHOD__,
2866 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2867 ) {
2868 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
2869 // on only the master (without needing row-based-replication). It also makes it easy to
2870 // know how big the INSERT is going to be.
2871 $fields = [];
2872 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
2873 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
2874 }
2875 $selectOptions[] = 'FOR UPDATE';
2876 $res = $this->select(
2877 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
2878 );
2879 if ( !$res ) {
2880 return false;
2881 }
2882
2883 try {
2884 $affectedRowCount = 0;
2885 $this->startAtomic( $fname, self::ATOMIC_CANCELABLE );
2886 $rows = [];
2887 $ok = true;
2888 foreach ( $res as $row ) {
2889 $rows[] = (array)$row;
2890
2891 // Avoid inserts that are too huge
2892 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize ) {
2893 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
2894 if ( !$ok ) {
2895 break;
2896 }
2897 $affectedRowCount += $this->affectedRows();
2898 $rows = [];
2899 }
2900 }
2901 if ( $rows && $ok ) {
2902 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
2903 if ( $ok ) {
2904 $affectedRowCount += $this->affectedRows();
2905 }
2906 }
2907 if ( $ok ) {
2908 $this->endAtomic( $fname );
2909 $this->affectedRowCount = $affectedRowCount;
2910 } else {
2911 $this->cancelAtomic( $fname );
2912 }
2913 return $ok;
2914 } catch ( Exception $e ) {
2915 $this->cancelAtomic( $fname );
2916 throw $e;
2917 }
2918 }
2919
2920 /**
2921 * Native server-side implementation of insertSelect() for situations where
2922 * we don't want to select everything into memory
2923 *
2924 * @see IDatabase::insertSelect()
2925 * @param string $destTable
2926 * @param string|array $srcTable
2927 * @param array $varMap
2928 * @param array $conds
2929 * @param string $fname
2930 * @param array $insertOptions
2931 * @param array $selectOptions
2932 * @param array $selectJoinConds
2933 * @return bool
2934 */
2935 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
2936 $fname = __METHOD__,
2937 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2938 ) {
2939 $destTable = $this->tableName( $destTable );
2940
2941 if ( !is_array( $insertOptions ) ) {
2942 $insertOptions = [ $insertOptions ];
2943 }
2944
2945 $insertOptions = $this->makeInsertOptions( $insertOptions );
2946
2947 $selectSql = $this->selectSQLText(
2948 $srcTable,
2949 array_values( $varMap ),
2950 $conds,
2951 $fname,
2952 $selectOptions,
2953 $selectJoinConds
2954 );
2955
2956 $sql = "INSERT $insertOptions" .
2957 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
2958 $selectSql;
2959
2960 return $this->query( $sql, $fname );
2961 }
2962
2963 /**
2964 * Construct a LIMIT query with optional offset. This is used for query
2965 * pages. The SQL should be adjusted so that only the first $limit rows
2966 * are returned. If $offset is provided as well, then the first $offset
2967 * rows should be discarded, and the next $limit rows should be returned.
2968 * If the result of the query is not ordered, then the rows to be returned
2969 * are theoretically arbitrary.
2970 *
2971 * $sql is expected to be a SELECT, if that makes a difference.
2972 *
2973 * The version provided by default works in MySQL and SQLite. It will very
2974 * likely need to be overridden for most other DBMSes.
2975 *
2976 * @param string $sql SQL query we will append the limit too
2977 * @param int $limit The SQL limit
2978 * @param int|bool $offset The SQL offset (default false)
2979 * @throws DBUnexpectedError
2980 * @return string
2981 */
2982 public function limitResult( $sql, $limit, $offset = false ) {
2983 if ( !is_numeric( $limit ) ) {
2984 throw new DBUnexpectedError( $this,
2985 "Invalid non-numeric limit passed to limitResult()\n" );
2986 }
2987
2988 return "$sql LIMIT "
2989 . ( ( is_numeric( $offset ) && $offset != 0 ) ? "{$offset}," : "" )
2990 . "{$limit} ";
2991 }
2992
2993 public function unionSupportsOrderAndLimit() {
2994 return true; // True for almost every DB supported
2995 }
2996
2997 public function unionQueries( $sqls, $all ) {
2998 $glue = $all ? ') UNION ALL (' : ') UNION (';
2999
3000 return '(' . implode( $glue, $sqls ) . ')';
3001 }
3002
3003 public function unionConditionPermutations(
3004 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__,
3005 $options = [], $join_conds = []
3006 ) {
3007 // First, build the Cartesian product of $permute_conds
3008 $conds = [ [] ];
3009 foreach ( $permute_conds as $field => $values ) {
3010 if ( !$values ) {
3011 // Skip empty $values
3012 continue;
3013 }
3014 $values = array_unique( $values ); // For sanity
3015 $newConds = [];
3016 foreach ( $conds as $cond ) {
3017 foreach ( $values as $value ) {
3018 $cond[$field] = $value;
3019 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
3020 }
3021 }
3022 $conds = $newConds;
3023 }
3024
3025 $extra_conds = $extra_conds === '' ? [] : (array)$extra_conds;
3026
3027 // If there's just one condition and no subordering, hand off to
3028 // selectSQLText directly.
3029 if ( count( $conds ) === 1 &&
3030 ( !isset( $options['INNER ORDER BY'] ) || !$this->unionSupportsOrderAndLimit() )
3031 ) {
3032 return $this->selectSQLText(
3033 $table, $vars, $conds[0] + $extra_conds, $fname, $options, $join_conds
3034 );
3035 }
3036
3037 // Otherwise, we need to pull out the order and limit to apply after
3038 // the union. Then build the SQL queries for each set of conditions in
3039 // $conds. Then union them together (using UNION ALL, because the
3040 // product *should* already be distinct).
3041 $orderBy = $this->makeOrderBy( $options );
3042 $limit = isset( $options['LIMIT'] ) ? $options['LIMIT'] : null;
3043 $offset = isset( $options['OFFSET'] ) ? $options['OFFSET'] : false;
3044 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
3045 if ( !$this->unionSupportsOrderAndLimit() ) {
3046 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
3047 } else {
3048 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
3049 $options['ORDER BY'] = $options['INNER ORDER BY'];
3050 }
3051 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
3052 // We need to increase the limit by the offset rather than
3053 // using the offset directly, otherwise it'll skip incorrectly
3054 // in the subqueries.
3055 $options['LIMIT'] = $limit + $offset;
3056 unset( $options['OFFSET'] );
3057 }
3058 }
3059
3060 $sqls = [];
3061 foreach ( $conds as $cond ) {
3062 $sqls[] = $this->selectSQLText(
3063 $table, $vars, $cond + $extra_conds, $fname, $options, $join_conds
3064 );
3065 }
3066 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
3067 if ( $limit !== null ) {
3068 $sql = $this->limitResult( $sql, $limit, $offset );
3069 }
3070
3071 return $sql;
3072 }
3073
3074 public function conditional( $cond, $trueVal, $falseVal ) {
3075 if ( is_array( $cond ) ) {
3076 $cond = $this->makeList( $cond, self::LIST_AND );
3077 }
3078
3079 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
3080 }
3081
3082 public function strreplace( $orig, $old, $new ) {
3083 return "REPLACE({$orig}, {$old}, {$new})";
3084 }
3085
3086 public function getServerUptime() {
3087 return 0;
3088 }
3089
3090 public function wasDeadlock() {
3091 return false;
3092 }
3093
3094 public function wasLockTimeout() {
3095 return false;
3096 }
3097
3098 public function wasConnectionLoss() {
3099 return $this->wasConnectionError( $this->lastErrno() );
3100 }
3101
3102 public function wasReadOnlyError() {
3103 return false;
3104 }
3105
3106 public function wasErrorReissuable() {
3107 return (
3108 $this->wasDeadlock() ||
3109 $this->wasLockTimeout() ||
3110 $this->wasConnectionLoss()
3111 );
3112 }
3113
3114 /**
3115 * Do not use this method outside of Database/DBError classes
3116 *
3117 * @param int|string $errno
3118 * @return bool Whether the given query error was a connection drop
3119 */
3120 public function wasConnectionError( $errno ) {
3121 return false;
3122 }
3123
3124 /**
3125 * @return bool Whether it is safe to assume the given error only caused statement rollback
3126 * @note This is for backwards compatibility for callers catching DBError exceptions in
3127 * order to ignore problems like duplicate key errors or foriegn key violations
3128 * @since 1.31
3129 */
3130 protected function wasKnownStatementRollbackError() {
3131 return false; // don't know; it could have caused a transaction rollback
3132 }
3133
3134 public function deadlockLoop() {
3135 $args = func_get_args();
3136 $function = array_shift( $args );
3137 $tries = self::DEADLOCK_TRIES;
3138
3139 $this->begin( __METHOD__ );
3140
3141 $retVal = null;
3142 /** @var Exception $e */
3143 $e = null;
3144 do {
3145 try {
3146 $retVal = call_user_func_array( $function, $args );
3147 break;
3148 } catch ( DBQueryError $e ) {
3149 if ( $this->wasDeadlock() ) {
3150 // Retry after a randomized delay
3151 usleep( mt_rand( self::DEADLOCK_DELAY_MIN, self::DEADLOCK_DELAY_MAX ) );
3152 } else {
3153 // Throw the error back up
3154 throw $e;
3155 }
3156 }
3157 } while ( --$tries > 0 );
3158
3159 if ( $tries <= 0 ) {
3160 // Too many deadlocks; give up
3161 $this->rollback( __METHOD__ );
3162 throw $e;
3163 } else {
3164 $this->commit( __METHOD__ );
3165
3166 return $retVal;
3167 }
3168 }
3169
3170 public function masterPosWait( DBMasterPos $pos, $timeout ) {
3171 # Real waits are implemented in the subclass.
3172 return 0;
3173 }
3174
3175 public function getReplicaPos() {
3176 # Stub
3177 return false;
3178 }
3179
3180 public function getMasterPos() {
3181 # Stub
3182 return false;
3183 }
3184
3185 public function serverIsReadOnly() {
3186 return false;
3187 }
3188
3189 final public function onTransactionResolution( callable $callback, $fname = __METHOD__ ) {
3190 if ( !$this->trxLevel ) {
3191 throw new DBUnexpectedError( $this, "No transaction is active." );
3192 }
3193 $this->trxEndCallbacks[] = [ $callback, $fname ];
3194 }
3195
3196 final public function onTransactionIdle( callable $callback, $fname = __METHOD__ ) {
3197 if ( !$this->trxLevel && $this->getTransactionRoundId() ) {
3198 // Start an implicit transaction similar to how query() does
3199 $this->begin( __METHOD__, self::TRANSACTION_INTERNAL );
3200 $this->trxAutomatic = true;
3201 }
3202
3203 $this->trxIdleCallbacks[] = [ $callback, $fname ];
3204 if ( !$this->trxLevel ) {
3205 $this->runOnTransactionIdleCallbacks( self::TRIGGER_IDLE );
3206 }
3207 }
3208
3209 final public function onTransactionPreCommitOrIdle( callable $callback, $fname = __METHOD__ ) {
3210 if ( !$this->trxLevel && $this->getTransactionRoundId() ) {
3211 // Start an implicit transaction similar to how query() does
3212 $this->begin( __METHOD__, self::TRANSACTION_INTERNAL );
3213 $this->trxAutomatic = true;
3214 }
3215
3216 if ( $this->trxLevel ) {
3217 $this->trxPreCommitCallbacks[] = [ $callback, $fname ];
3218 } else {
3219 // No transaction is active nor will start implicitly, so make one for this callback
3220 $this->startAtomic( __METHOD__, self::ATOMIC_CANCELABLE );
3221 try {
3222 call_user_func( $callback );
3223 $this->endAtomic( __METHOD__ );
3224 } catch ( Exception $e ) {
3225 $this->cancelAtomic( __METHOD__ );
3226 throw $e;
3227 }
3228 }
3229 }
3230
3231 final public function setTransactionListener( $name, callable $callback = null ) {
3232 if ( $callback ) {
3233 $this->trxRecurringCallbacks[$name] = $callback;
3234 } else {
3235 unset( $this->trxRecurringCallbacks[$name] );
3236 }
3237 }
3238
3239 /**
3240 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3241 *
3242 * This method should not be used outside of Database/LoadBalancer
3243 *
3244 * @param bool $suppress
3245 * @since 1.28
3246 */
3247 final public function setTrxEndCallbackSuppression( $suppress ) {
3248 $this->trxEndCallbacksSuppressed = $suppress;
3249 }
3250
3251 /**
3252 * Actually run and consume any "on transaction idle/resolution" callbacks.
3253 *
3254 * This method should not be used outside of Database/LoadBalancer
3255 *
3256 * @param int $trigger IDatabase::TRIGGER_* constant
3257 * @since 1.20
3258 * @throws Exception
3259 */
3260 public function runOnTransactionIdleCallbacks( $trigger ) {
3261 if ( $this->trxEndCallbacksSuppressed ) {
3262 return;
3263 }
3264
3265 $autoTrx = $this->getFlag( self::DBO_TRX ); // automatic begin() enabled?
3266 /** @var Exception $e */
3267 $e = null; // first exception
3268 do { // callbacks may add callbacks :)
3269 $callbacks = array_merge(
3270 $this->trxIdleCallbacks,
3271 $this->trxEndCallbacks // include "transaction resolution" callbacks
3272 );
3273 $this->trxIdleCallbacks = []; // consumed (and recursion guard)
3274 $this->trxEndCallbacks = []; // consumed (recursion guard)
3275 foreach ( $callbacks as $callback ) {
3276 try {
3277 list( $phpCallback ) = $callback;
3278 $this->clearFlag( self::DBO_TRX ); // make each query its own transaction
3279 call_user_func_array( $phpCallback, [ $trigger ] );
3280 if ( $autoTrx ) {
3281 $this->setFlag( self::DBO_TRX ); // restore automatic begin()
3282 } else {
3283 $this->clearFlag( self::DBO_TRX ); // restore auto-commit
3284 }
3285 } catch ( Exception $ex ) {
3286 call_user_func( $this->errorLogger, $ex );
3287 $e = $e ?: $ex;
3288 // Some callbacks may use startAtomic/endAtomic, so make sure
3289 // their transactions are ended so other callbacks don't fail
3290 if ( $this->trxLevel() ) {
3291 $this->rollback( __METHOD__, self::FLUSHING_INTERNAL );
3292 }
3293 }
3294 }
3295 } while ( count( $this->trxIdleCallbacks ) );
3296
3297 if ( $e instanceof Exception ) {
3298 throw $e; // re-throw any first exception
3299 }
3300 }
3301
3302 /**
3303 * Actually run and consume any "on transaction pre-commit" callbacks.
3304 *
3305 * This method should not be used outside of Database/LoadBalancer
3306 *
3307 * @since 1.22
3308 * @throws Exception
3309 */
3310 public function runOnTransactionPreCommitCallbacks() {
3311 $e = null; // first exception
3312 do { // callbacks may add callbacks :)
3313 $callbacks = $this->trxPreCommitCallbacks;
3314 $this->trxPreCommitCallbacks = []; // consumed (and recursion guard)
3315 foreach ( $callbacks as $callback ) {
3316 try {
3317 list( $phpCallback ) = $callback;
3318 call_user_func( $phpCallback );
3319 } catch ( Exception $ex ) {
3320 call_user_func( $this->errorLogger, $ex );
3321 $e = $e ?: $ex;
3322 }
3323 }
3324 } while ( count( $this->trxPreCommitCallbacks ) );
3325
3326 if ( $e instanceof Exception ) {
3327 throw $e; // re-throw any first exception
3328 }
3329 }
3330
3331 /**
3332 * Actually run any "transaction listener" callbacks.
3333 *
3334 * This method should not be used outside of Database/LoadBalancer
3335 *
3336 * @param int $trigger IDatabase::TRIGGER_* constant
3337 * @throws Exception
3338 * @since 1.20
3339 */
3340 public function runTransactionListenerCallbacks( $trigger ) {
3341 if ( $this->trxEndCallbacksSuppressed ) {
3342 return;
3343 }
3344
3345 /** @var Exception $e */
3346 $e = null; // first exception
3347
3348 foreach ( $this->trxRecurringCallbacks as $phpCallback ) {
3349 try {
3350 $phpCallback( $trigger, $this );
3351 } catch ( Exception $ex ) {
3352 call_user_func( $this->errorLogger, $ex );
3353 $e = $e ?: $ex;
3354 }
3355 }
3356
3357 if ( $e instanceof Exception ) {
3358 throw $e; // re-throw any first exception
3359 }
3360 }
3361
3362 /**
3363 * Create a savepoint
3364 *
3365 * This is used internally to implement atomic sections. It should not be
3366 * used otherwise.
3367 *
3368 * @since 1.31
3369 * @param string $identifier Identifier for the savepoint
3370 * @param string $fname Calling function name
3371 */
3372 protected function doSavepoint( $identifier, $fname ) {
3373 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3374 }
3375
3376 /**
3377 * Release a savepoint
3378 *
3379 * This is used internally to implement atomic sections. It should not be
3380 * used otherwise.
3381 *
3382 * @since 1.31
3383 * @param string $identifier Identifier for the savepoint
3384 * @param string $fname Calling function name
3385 */
3386 protected function doReleaseSavepoint( $identifier, $fname ) {
3387 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3388 }
3389
3390 /**
3391 * Rollback to a savepoint
3392 *
3393 * This is used internally to implement atomic sections. It should not be
3394 * used otherwise.
3395 *
3396 * @since 1.31
3397 * @param string $identifier Identifier for the savepoint
3398 * @param string $fname Calling function name
3399 */
3400 protected function doRollbackToSavepoint( $identifier, $fname ) {
3401 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3402 }
3403
3404 final public function startAtomic(
3405 $fname = __METHOD__, $cancelable = self::ATOMIC_NOT_CANCELABLE
3406 ) {
3407 $savepointId = $cancelable === self::ATOMIC_CANCELABLE ? 'n/a' : null;
3408 if ( !$this->trxLevel ) {
3409 $this->begin( $fname, self::TRANSACTION_INTERNAL );
3410 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3411 // in all changes being in one transaction to keep requests transactional.
3412 if ( !$this->getFlag( self::DBO_TRX ) ) {
3413 $this->trxAutomaticAtomic = true;
3414 }
3415 } elseif ( $cancelable === self::ATOMIC_CANCELABLE ) {
3416 $savepointId = 'wikimedia_rdbms_atomic' . ++$this->trxAtomicCounter;
3417 if ( strlen( $savepointId ) > 30 ) { // 30 == Oracle's identifier length limit (pre 12c)
3418 $this->queryLogger->warning(
3419 'There have been an excessively large number of atomic sections in a transaction'
3420 . " started by $this->trxFname, reusing IDs (at $fname)",
3421 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
3422 );
3423 $this->trxAtomicCounter = 0;
3424 $savepointId = 'wikimedia_rdbms_atomic' . ++$this->trxAtomicCounter;
3425 }
3426 $this->doSavepoint( $savepointId, $fname );
3427 }
3428
3429 $this->trxAtomicLevels[] = [ $fname, $savepointId ];
3430 }
3431
3432 final public function endAtomic( $fname = __METHOD__ ) {
3433 if ( !$this->trxLevel ) {
3434 throw new DBUnexpectedError( $this, "No atomic transaction is open (got $fname)." );
3435 }
3436
3437 list( $savedFname, $savepointId ) = $this->trxAtomicLevels
3438 ? array_pop( $this->trxAtomicLevels ) : [ null, null ];
3439 if ( $savedFname !== $fname ) {
3440 throw new DBUnexpectedError( $this, "Invalid atomic section ended (got $fname)." );
3441 }
3442
3443 if ( !$this->trxAtomicLevels && $this->trxAutomaticAtomic ) {
3444 $this->commit( $fname, self::FLUSHING_INTERNAL );
3445 } elseif ( $savepointId && $savepointId !== 'n/a' ) {
3446 $this->doReleaseSavepoint( $savepointId, $fname );
3447 }
3448 }
3449
3450 final public function cancelAtomic( $fname = __METHOD__ ) {
3451 if ( !$this->trxLevel ) {
3452 throw new DBUnexpectedError( $this, "No atomic transaction is open (got $fname)." );
3453 }
3454
3455 list( $savedFname, $savepointId ) = $this->trxAtomicLevels
3456 ? array_pop( $this->trxAtomicLevels ) : [ null, null ];
3457 if ( $savedFname !== $fname ) {
3458 throw new DBUnexpectedError( $this, "Invalid atomic section ended (got $fname)." );
3459 }
3460 if ( !$savepointId ) {
3461 throw new DBUnexpectedError( $this, "Uncancelable atomic section canceled (got $fname)." );
3462 }
3463
3464 if ( !$this->trxAtomicLevels && $this->trxAutomaticAtomic ) {
3465 $this->rollback( $fname, self::FLUSHING_INTERNAL );
3466 } elseif ( $savepointId !== 'n/a' ) {
3467 $this->doRollbackToSavepoint( $savepointId, $fname );
3468 $this->trxStatus = self::STATUS_TRX_OK; // no exception; recovered
3469 }
3470
3471 $this->affectedRowCount = 0; // for the sake of consistency
3472 }
3473
3474 final public function doAtomicSection( $fname, callable $callback ) {
3475 $this->startAtomic( $fname, self::ATOMIC_CANCELABLE );
3476 try {
3477 $res = call_user_func_array( $callback, [ $this, $fname ] );
3478 } catch ( Exception $e ) {
3479 $this->cancelAtomic( $fname );
3480 throw $e;
3481 }
3482 $this->endAtomic( $fname );
3483
3484 return $res;
3485 }
3486
3487 final public function begin( $fname = __METHOD__, $mode = self::TRANSACTION_EXPLICIT ) {
3488 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3489 if ( $this->trxLevel ) {
3490 if ( $this->trxAtomicLevels ) {
3491 $levels = $this->flatAtomicSectionList();
3492 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
3493 throw new DBUnexpectedError( $this, $msg );
3494 } elseif ( !$this->trxAutomatic ) {
3495 $msg = "$fname: Explicit transaction already active (from {$this->trxFname}).";
3496 throw new DBUnexpectedError( $this, $msg );
3497 } else {
3498 $msg = "$fname: Implicit transaction already active (from {$this->trxFname}).";
3499 throw new DBUnexpectedError( $this, $msg );
3500 }
3501 } elseif ( $this->getFlag( self::DBO_TRX ) && $mode !== self::TRANSACTION_INTERNAL ) {
3502 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
3503 throw new DBUnexpectedError( $this, $msg );
3504 }
3505
3506 // Avoid fatals if close() was called
3507 $this->assertOpen();
3508
3509 $this->doBegin( $fname );
3510 $this->trxStatus = self::STATUS_TRX_OK;
3511 $this->trxAtomicCounter = 0;
3512 $this->trxTimestamp = microtime( true );
3513 $this->trxFname = $fname;
3514 $this->trxDoneWrites = false;
3515 $this->trxAutomaticAtomic = false;
3516 $this->trxAtomicLevels = [];
3517 $this->trxShortId = sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3518 $this->trxWriteDuration = 0.0;
3519 $this->trxWriteQueryCount = 0;
3520 $this->trxWriteAffectedRows = 0;
3521 $this->trxWriteAdjDuration = 0.0;
3522 $this->trxWriteAdjQueryCount = 0;
3523 $this->trxWriteCallers = [];
3524 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
3525 // Get an estimate of the replication lag before any such queries.
3526 $this->trxReplicaLag = null; // clear cached value first
3527 $this->trxReplicaLag = $this->getApproximateLagStatus()['lag'];
3528 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3529 // caller will think its OK to muck around with the transaction just because startAtomic()
3530 // has not yet completed (e.g. setting trxAtomicLevels).
3531 $this->trxAutomatic = ( $mode === self::TRANSACTION_INTERNAL );
3532 }
3533
3534 /**
3535 * Issues the BEGIN command to the database server.
3536 *
3537 * @see Database::begin()
3538 * @param string $fname
3539 */
3540 protected function doBegin( $fname ) {
3541 $this->query( 'BEGIN', $fname );
3542 $this->trxLevel = 1;
3543 }
3544
3545 final public function commit( $fname = __METHOD__, $flush = '' ) {
3546 if ( $this->trxLevel && $this->trxAtomicLevels ) {
3547 // There are still atomic sections open. This cannot be ignored
3548 $levels = $this->flatAtomicSectionList();
3549 throw new DBUnexpectedError(
3550 $this,
3551 "$fname: Got COMMIT while atomic sections $levels are still open."
3552 );
3553 }
3554
3555 if ( $flush === self::FLUSHING_INTERNAL || $flush === self::FLUSHING_ALL_PEERS ) {
3556 if ( !$this->trxLevel ) {
3557 return; // nothing to do
3558 } elseif ( !$this->trxAutomatic ) {
3559 throw new DBUnexpectedError(
3560 $this,
3561 "$fname: Flushing an explicit transaction, getting out of sync."
3562 );
3563 }
3564 } else {
3565 if ( !$this->trxLevel ) {
3566 $this->queryLogger->error(
3567 "$fname: No transaction to commit, something got out of sync." );
3568 return; // nothing to do
3569 } elseif ( $this->trxAutomatic ) {
3570 throw new DBUnexpectedError(
3571 $this,
3572 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)."
3573 );
3574 }
3575 }
3576
3577 // Avoid fatals if close() was called
3578 $this->assertOpen();
3579
3580 $this->runOnTransactionPreCommitCallbacks();
3581 $writeTime = $this->pendingWriteQueryDuration( self::ESTIMATE_DB_APPLY );
3582 $this->doCommit( $fname );
3583 $this->trxStatus = self::STATUS_TRX_NONE;
3584 if ( $this->trxDoneWrites ) {
3585 $this->lastWriteTime = microtime( true );
3586 $this->trxProfiler->transactionWritingOut(
3587 $this->server,
3588 $this->dbName,
3589 $this->trxShortId,
3590 $writeTime,
3591 $this->trxWriteAffectedRows
3592 );
3593 }
3594
3595 $this->runOnTransactionIdleCallbacks( self::TRIGGER_COMMIT );
3596 $this->runTransactionListenerCallbacks( self::TRIGGER_COMMIT );
3597 }
3598
3599 /**
3600 * Issues the COMMIT command to the database server.
3601 *
3602 * @see Database::commit()
3603 * @param string $fname
3604 */
3605 protected function doCommit( $fname ) {
3606 if ( $this->trxLevel ) {
3607 $this->query( 'COMMIT', $fname );
3608 $this->trxLevel = 0;
3609 }
3610 }
3611
3612 final public function rollback( $fname = __METHOD__, $flush = '' ) {
3613 $trxActive = $this->trxLevel;
3614
3615 if ( $flush !== self::FLUSHING_INTERNAL && $flush !== self::FLUSHING_ALL_PEERS ) {
3616 if ( $this->getFlag( self::DBO_TRX ) ) {
3617 throw new DBUnexpectedError(
3618 $this,
3619 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)."
3620 );
3621 }
3622 }
3623
3624 if ( $trxActive ) {
3625 // Avoid fatals if close() was called
3626 $this->assertOpen();
3627
3628 $this->doRollback( $fname );
3629 $this->trxStatus = self::STATUS_TRX_NONE;
3630 $this->trxAtomicLevels = [];
3631 if ( $this->trxDoneWrites ) {
3632 $this->trxProfiler->transactionWritingOut(
3633 $this->server,
3634 $this->dbName,
3635 $this->trxShortId
3636 );
3637 }
3638 }
3639
3640 // Clear any commit-dependant callbacks. They might even be present
3641 // only due to transaction rounds, with no SQL transaction being active
3642 $this->trxIdleCallbacks = [];
3643 $this->trxPreCommitCallbacks = [];
3644
3645 if ( $trxActive ) {
3646 try {
3647 $this->runOnTransactionIdleCallbacks( self::TRIGGER_ROLLBACK );
3648 } catch ( Exception $e ) {
3649 // already logged; finish and let LoadBalancer move on during mass-rollback
3650 }
3651 try {
3652 $this->runTransactionListenerCallbacks( self::TRIGGER_ROLLBACK );
3653 } catch ( Exception $e ) {
3654 // already logged; let LoadBalancer move on during mass-rollback
3655 }
3656
3657 $this->affectedRowCount = 0; // for the sake of consistency
3658 }
3659 }
3660
3661 /**
3662 * Issues the ROLLBACK command to the database server.
3663 *
3664 * @see Database::rollback()
3665 * @param string $fname
3666 */
3667 protected function doRollback( $fname ) {
3668 if ( $this->trxLevel ) {
3669 # Disconnects cause rollback anyway, so ignore those errors
3670 $ignoreErrors = true;
3671 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
3672 $this->trxLevel = 0;
3673 }
3674 }
3675
3676 public function flushSnapshot( $fname = __METHOD__ ) {
3677 if ( $this->writesOrCallbacksPending() || $this->explicitTrxActive() ) {
3678 // This only flushes transactions to clear snapshots, not to write data
3679 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
3680 throw new DBUnexpectedError(
3681 $this,
3682 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
3683 );
3684 }
3685
3686 $this->commit( $fname, self::FLUSHING_INTERNAL );
3687 }
3688
3689 public function explicitTrxActive() {
3690 return $this->trxLevel && ( $this->trxAtomicLevels || !$this->trxAutomatic );
3691 }
3692
3693 public function duplicateTableStructure(
3694 $oldName, $newName, $temporary = false, $fname = __METHOD__
3695 ) {
3696 throw new RuntimeException( __METHOD__ . ' is not implemented in descendant class' );
3697 }
3698
3699 public function listTables( $prefix = null, $fname = __METHOD__ ) {
3700 throw new RuntimeException( __METHOD__ . ' is not implemented in descendant class' );
3701 }
3702
3703 public function listViews( $prefix = null, $fname = __METHOD__ ) {
3704 throw new RuntimeException( __METHOD__ . ' is not implemented in descendant class' );
3705 }
3706
3707 public function timestamp( $ts = 0 ) {
3708 $t = new ConvertibleTimestamp( $ts );
3709 // Let errors bubble up to avoid putting garbage in the DB
3710 return $t->getTimestamp( TS_MW );
3711 }
3712
3713 public function timestampOrNull( $ts = null ) {
3714 if ( is_null( $ts ) ) {
3715 return null;
3716 } else {
3717 return $this->timestamp( $ts );
3718 }
3719 }
3720
3721 public function affectedRows() {
3722 return ( $this->affectedRowCount === null )
3723 ? $this->fetchAffectedRowCount() // default to driver value
3724 : $this->affectedRowCount;
3725 }
3726
3727 /**
3728 * @return int Number of retrieved rows according to the driver
3729 */
3730 abstract protected function fetchAffectedRowCount();
3731
3732 /**
3733 * Take the result from a query, and wrap it in a ResultWrapper if
3734 * necessary. Boolean values are passed through as is, to indicate success
3735 * of write queries or failure.
3736 *
3737 * Once upon a time, Database::query() returned a bare MySQL result
3738 * resource, and it was necessary to call this function to convert it to
3739 * a wrapper. Nowadays, raw database objects are never exposed to external
3740 * callers, so this is unnecessary in external code.
3741 *
3742 * @param bool|ResultWrapper|resource|object $result
3743 * @return bool|ResultWrapper
3744 */
3745 protected function resultObject( $result ) {
3746 if ( !$result ) {
3747 return false;
3748 } elseif ( $result instanceof ResultWrapper ) {
3749 return $result;
3750 } elseif ( $result === true ) {
3751 // Successful write query
3752 return $result;
3753 } else {
3754 return new ResultWrapper( $this, $result );
3755 }
3756 }
3757
3758 public function ping( &$rtt = null ) {
3759 // Avoid hitting the server if it was hit recently
3760 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing ) < self::PING_TTL ) {
3761 if ( !func_num_args() || $this->rttEstimate > 0 ) {
3762 $rtt = $this->rttEstimate;
3763 return true; // don't care about $rtt
3764 }
3765 }
3766
3767 // This will reconnect if possible or return false if not
3768 $this->clearFlag( self::DBO_TRX, self::REMEMBER_PRIOR );
3769 $ok = ( $this->query( self::PING_QUERY, __METHOD__, true ) !== false );
3770 $this->restoreFlags( self::RESTORE_PRIOR );
3771
3772 if ( $ok ) {
3773 $rtt = $this->rttEstimate;
3774 }
3775
3776 return $ok;
3777 }
3778
3779 /**
3780 * Close any existing (dead) database connection and open a new connection
3781 *
3782 * @param string $fname
3783 * @return bool True if new connection is opened successfully, false if error
3784 */
3785 protected function replaceLostConnection( $fname ) {
3786 $this->closeConnection();
3787 $this->opened = false;
3788 $this->conn = false;
3789 try {
3790 $this->open( $this->server, $this->user, $this->password, $this->dbName );
3791 $this->lastPing = microtime( true );
3792 $ok = true;
3793
3794 $this->connLogger->warning(
3795 $fname . ': lost connection to {dbserver}; reconnected',
3796 [
3797 'dbserver' => $this->getServer(),
3798 'trace' => ( new RuntimeException() )->getTraceAsString()
3799 ]
3800 );
3801 } catch ( DBConnectionError $e ) {
3802 $ok = false;
3803
3804 $this->connLogger->error(
3805 $fname . ': lost connection to {dbserver} permanently',
3806 [ 'dbserver' => $this->getServer() ]
3807 );
3808 }
3809
3810 $this->handleSessionLoss();
3811
3812 return $ok;
3813 }
3814
3815 public function getSessionLagStatus() {
3816 return $this->getRecordedTransactionLagStatus() ?: $this->getApproximateLagStatus();
3817 }
3818
3819 /**
3820 * Get the replica DB lag when the current transaction started
3821 *
3822 * This is useful when transactions might use snapshot isolation
3823 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
3824 * is this lag plus transaction duration. If they don't, it is still
3825 * safe to be pessimistic. This returns null if there is no transaction.
3826 *
3827 * This returns null if the lag status for this transaction was not yet recorded.
3828 *
3829 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
3830 * @since 1.27
3831 */
3832 final protected function getRecordedTransactionLagStatus() {
3833 return ( $this->trxLevel && $this->trxReplicaLag !== null )
3834 ? [ 'lag' => $this->trxReplicaLag, 'since' => $this->trxTimestamp() ]
3835 : null;
3836 }
3837
3838 /**
3839 * Get a replica DB lag estimate for this server
3840 *
3841 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
3842 * @since 1.27
3843 */
3844 protected function getApproximateLagStatus() {
3845 return [
3846 'lag' => $this->getLBInfo( 'replica' ) ? $this->getLag() : 0,
3847 'since' => microtime( true )
3848 ];
3849 }
3850
3851 /**
3852 * Merge the result of getSessionLagStatus() for several DBs
3853 * using the most pessimistic values to estimate the lag of
3854 * any data derived from them in combination
3855 *
3856 * This is information is useful for caching modules
3857 *
3858 * @see WANObjectCache::set()
3859 * @see WANObjectCache::getWithSetCallback()
3860 *
3861 * @param IDatabase $db1
3862 * @param IDatabase $db2 [optional]
3863 * @return array Map of values:
3864 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
3865 * - since: oldest UNIX timestamp of any of the DB lag estimates
3866 * - pending: whether any of the DBs have uncommitted changes
3867 * @throws DBError
3868 * @since 1.27
3869 */
3870 public static function getCacheSetOptions( IDatabase $db1, IDatabase $db2 = null ) {
3871 $res = [ 'lag' => 0, 'since' => INF, 'pending' => false ];
3872 foreach ( func_get_args() as $db ) {
3873 /** @var IDatabase $db */
3874 $status = $db->getSessionLagStatus();
3875 if ( $status['lag'] === false ) {
3876 $res['lag'] = false;
3877 } elseif ( $res['lag'] !== false ) {
3878 $res['lag'] = max( $res['lag'], $status['lag'] );
3879 }
3880 $res['since'] = min( $res['since'], $status['since'] );
3881 $res['pending'] = $res['pending'] ?: $db->writesPending();
3882 }
3883
3884 return $res;
3885 }
3886
3887 public function getLag() {
3888 return 0;
3889 }
3890
3891 public function maxListLen() {
3892 return 0;
3893 }
3894
3895 public function encodeBlob( $b ) {
3896 return $b;
3897 }
3898
3899 public function decodeBlob( $b ) {
3900 if ( $b instanceof Blob ) {
3901 $b = $b->fetch();
3902 }
3903 return $b;
3904 }
3905
3906 public function setSessionOptions( array $options ) {
3907 }
3908
3909 public function sourceFile(
3910 $filename,
3911 callable $lineCallback = null,
3912 callable $resultCallback = null,
3913 $fname = false,
3914 callable $inputCallback = null
3915 ) {
3916 Wikimedia\suppressWarnings();
3917 $fp = fopen( $filename, 'r' );
3918 Wikimedia\restoreWarnings();
3919
3920 if ( false === $fp ) {
3921 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
3922 }
3923
3924 if ( !$fname ) {
3925 $fname = __METHOD__ . "( $filename )";
3926 }
3927
3928 try {
3929 $error = $this->sourceStream(
3930 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
3931 } catch ( Exception $e ) {
3932 fclose( $fp );
3933 throw $e;
3934 }
3935
3936 fclose( $fp );
3937
3938 return $error;
3939 }
3940
3941 public function setSchemaVars( $vars ) {
3942 $this->schemaVars = $vars;
3943 }
3944
3945 public function sourceStream(
3946 $fp,
3947 callable $lineCallback = null,
3948 callable $resultCallback = null,
3949 $fname = __METHOD__,
3950 callable $inputCallback = null
3951 ) {
3952 $delimiterReset = new ScopedCallback(
3953 function ( $delimiter ) {
3954 $this->delimiter = $delimiter;
3955 },
3956 [ $this->delimiter ]
3957 );
3958 $cmd = '';
3959
3960 while ( !feof( $fp ) ) {
3961 if ( $lineCallback ) {
3962 call_user_func( $lineCallback );
3963 }
3964
3965 $line = trim( fgets( $fp ) );
3966
3967 if ( $line == '' ) {
3968 continue;
3969 }
3970
3971 if ( '-' == $line[0] && '-' == $line[1] ) {
3972 continue;
3973 }
3974
3975 if ( $cmd != '' ) {
3976 $cmd .= ' ';
3977 }
3978
3979 $done = $this->streamStatementEnd( $cmd, $line );
3980
3981 $cmd .= "$line\n";
3982
3983 if ( $done || feof( $fp ) ) {
3984 $cmd = $this->replaceVars( $cmd );
3985
3986 if ( $inputCallback ) {
3987 $callbackResult = call_user_func( $inputCallback, $cmd );
3988
3989 if ( is_string( $callbackResult ) || !$callbackResult ) {
3990 $cmd = $callbackResult;
3991 }
3992 }
3993
3994 if ( $cmd ) {
3995 $res = $this->query( $cmd, $fname );
3996
3997 if ( $resultCallback ) {
3998 call_user_func( $resultCallback, $res, $this );
3999 }
4000
4001 if ( false === $res ) {
4002 $err = $this->lastError();
4003
4004 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
4005 }
4006 }
4007 $cmd = '';
4008 }
4009 }
4010
4011 ScopedCallback::consume( $delimiterReset );
4012 return true;
4013 }
4014
4015 /**
4016 * Called by sourceStream() to check if we've reached a statement end
4017 *
4018 * @param string &$sql SQL assembled so far
4019 * @param string &$newLine New line about to be added to $sql
4020 * @return bool Whether $newLine contains end of the statement
4021 */
4022 public function streamStatementEnd( &$sql, &$newLine ) {
4023 if ( $this->delimiter ) {
4024 $prev = $newLine;
4025 $newLine = preg_replace(
4026 '/' . preg_quote( $this->delimiter, '/' ) . '$/', '', $newLine );
4027 if ( $newLine != $prev ) {
4028 return true;
4029 }
4030 }
4031
4032 return false;
4033 }
4034
4035 /**
4036 * Database independent variable replacement. Replaces a set of variables
4037 * in an SQL statement with their contents as given by $this->getSchemaVars().
4038 *
4039 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
4040 *
4041 * - '{$var}' should be used for text and is passed through the database's
4042 * addQuotes method.
4043 * - `{$var}` should be used for identifiers (e.g. table and database names).
4044 * It is passed through the database's addIdentifierQuotes method which
4045 * can be overridden if the database uses something other than backticks.
4046 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
4047 * database's tableName method.
4048 * - / *i* / passes the name that follows through the database's indexName method.
4049 * - In all other cases, / *$var* / is left unencoded. Except for table options,
4050 * its use should be avoided. In 1.24 and older, string encoding was applied.
4051 *
4052 * @param string $ins SQL statement to replace variables in
4053 * @return string The new SQL statement with variables replaced
4054 */
4055 protected function replaceVars( $ins ) {
4056 $vars = $this->getSchemaVars();
4057 return preg_replace_callback(
4058 '!
4059 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
4060 \'\{\$ (\w+) }\' | # 3. addQuotes
4061 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
4062 /\*\$ (\w+) \*/ # 5. leave unencoded
4063 !x',
4064 function ( $m ) use ( $vars ) {
4065 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
4066 // check for both nonexistent keys *and* the empty string.
4067 if ( isset( $m[1] ) && $m[1] !== '' ) {
4068 if ( $m[1] === 'i' ) {
4069 return $this->indexName( $m[2] );
4070 } else {
4071 return $this->tableName( $m[2] );
4072 }
4073 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
4074 return $this->addQuotes( $vars[$m[3]] );
4075 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
4076 return $this->addIdentifierQuotes( $vars[$m[4]] );
4077 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
4078 return $vars[$m[5]];
4079 } else {
4080 return $m[0];
4081 }
4082 },
4083 $ins
4084 );
4085 }
4086
4087 /**
4088 * Get schema variables. If none have been set via setSchemaVars(), then
4089 * use some defaults from the current object.
4090 *
4091 * @return array
4092 */
4093 protected function getSchemaVars() {
4094 if ( $this->schemaVars ) {
4095 return $this->schemaVars;
4096 } else {
4097 return $this->getDefaultSchemaVars();
4098 }
4099 }
4100
4101 /**
4102 * Get schema variables to use if none have been set via setSchemaVars().
4103 *
4104 * Override this in derived classes to provide variables for tables.sql
4105 * and SQL patch files.
4106 *
4107 * @return array
4108 */
4109 protected function getDefaultSchemaVars() {
4110 return [];
4111 }
4112
4113 public function lockIsFree( $lockName, $method ) {
4114 // RDBMs methods for checking named locks may or may not count this thread itself.
4115 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4116 // the behavior choosen by the interface for this method.
4117 return !isset( $this->namedLocksHeld[$lockName] );
4118 }
4119
4120 public function lock( $lockName, $method, $timeout = 5 ) {
4121 $this->namedLocksHeld[$lockName] = 1;
4122
4123 return true;
4124 }
4125
4126 public function unlock( $lockName, $method ) {
4127 unset( $this->namedLocksHeld[$lockName] );
4128
4129 return true;
4130 }
4131
4132 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4133 if ( $this->writesOrCallbacksPending() ) {
4134 // This only flushes transactions to clear snapshots, not to write data
4135 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4136 throw new DBUnexpectedError(
4137 $this,
4138 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
4139 );
4140 }
4141
4142 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4143 return null;
4144 }
4145
4146 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4147 if ( $this->trxLevel() ) {
4148 // There is a good chance an exception was thrown, causing any early return
4149 // from the caller. Let any error handler get a chance to issue rollback().
4150 // If there isn't one, let the error bubble up and trigger server-side rollback.
4151 $this->onTransactionResolution(
4152 function () use ( $lockKey, $fname ) {
4153 $this->unlock( $lockKey, $fname );
4154 },
4155 $fname
4156 );
4157 } else {
4158 $this->unlock( $lockKey, $fname );
4159 }
4160 } );
4161
4162 $this->commit( $fname, self::FLUSHING_INTERNAL );
4163
4164 return $unlocker;
4165 }
4166
4167 public function namedLocksEnqueue() {
4168 return false;
4169 }
4170
4171 public function tableLocksHaveTransactionScope() {
4172 return true;
4173 }
4174
4175 final public function lockTables( array $read, array $write, $method ) {
4176 if ( $this->writesOrCallbacksPending() ) {
4177 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
4178 }
4179
4180 if ( $this->tableLocksHaveTransactionScope() ) {
4181 $this->startAtomic( $method );
4182 }
4183
4184 return $this->doLockTables( $read, $write, $method );
4185 }
4186
4187 /**
4188 * Helper function for lockTables() that handles the actual table locking
4189 *
4190 * @param array $read Array of tables to lock for read access
4191 * @param array $write Array of tables to lock for write access
4192 * @param string $method Name of caller
4193 * @return true
4194 */
4195 protected function doLockTables( array $read, array $write, $method ) {
4196 return true;
4197 }
4198
4199 final public function unlockTables( $method ) {
4200 if ( $this->tableLocksHaveTransactionScope() ) {
4201 $this->endAtomic( $method );
4202
4203 return true; // locks released on COMMIT/ROLLBACK
4204 }
4205
4206 return $this->doUnlockTables( $method );
4207 }
4208
4209 /**
4210 * Helper function for unlockTables() that handles the actual table unlocking
4211 *
4212 * @param string $method Name of caller
4213 * @return true
4214 */
4215 protected function doUnlockTables( $method ) {
4216 return true;
4217 }
4218
4219 /**
4220 * Delete a table
4221 * @param string $tableName
4222 * @param string $fName
4223 * @return bool|ResultWrapper
4224 * @since 1.18
4225 */
4226 public function dropTable( $tableName, $fName = __METHOD__ ) {
4227 if ( !$this->tableExists( $tableName, $fName ) ) {
4228 return false;
4229 }
4230 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4231
4232 return $this->query( $sql, $fName );
4233 }
4234
4235 public function getInfinity() {
4236 return 'infinity';
4237 }
4238
4239 public function encodeExpiry( $expiry ) {
4240 return ( $expiry == '' || $expiry == 'infinity' || $expiry == $this->getInfinity() )
4241 ? $this->getInfinity()
4242 : $this->timestamp( $expiry );
4243 }
4244
4245 public function decodeExpiry( $expiry, $format = TS_MW ) {
4246 if ( $expiry == '' || $expiry == 'infinity' || $expiry == $this->getInfinity() ) {
4247 return 'infinity';
4248 }
4249
4250 return ConvertibleTimestamp::convert( $format, $expiry );
4251 }
4252
4253 public function setBigSelects( $value = true ) {
4254 // no-op
4255 }
4256
4257 public function isReadOnly() {
4258 return ( $this->getReadOnlyReason() !== false );
4259 }
4260
4261 /**
4262 * @return string|bool Reason this DB is read-only or false if it is not
4263 */
4264 protected function getReadOnlyReason() {
4265 $reason = $this->getLBInfo( 'readOnlyReason' );
4266
4267 return is_string( $reason ) ? $reason : false;
4268 }
4269
4270 public function setTableAliases( array $aliases ) {
4271 $this->tableAliases = $aliases;
4272 }
4273
4274 public function setIndexAliases( array $aliases ) {
4275 $this->indexAliases = $aliases;
4276 }
4277
4278 /**
4279 * Get the underlying binding connection handle
4280 *
4281 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4282 * This catches broken callers than catch and ignore disconnection exceptions.
4283 * Unlike checking isOpen(), this is safe to call inside of open().
4284 *
4285 * @return mixed
4286 * @throws DBUnexpectedError
4287 * @since 1.26
4288 */
4289 protected function getBindingHandle() {
4290 if ( !$this->conn ) {
4291 throw new DBUnexpectedError(
4292 $this,
4293 'DB connection was already closed or the connection dropped.'
4294 );
4295 }
4296
4297 return $this->conn;
4298 }
4299
4300 /**
4301 * @since 1.19
4302 * @return string
4303 */
4304 public function __toString() {
4305 return (string)$this->conn;
4306 }
4307
4308 /**
4309 * Make sure that copies do not share the same client binding handle
4310 * @throws DBConnectionError
4311 */
4312 public function __clone() {
4313 $this->connLogger->warning(
4314 "Cloning " . static::class . " is not recomended; forking connection:\n" .
4315 ( new RuntimeException() )->getTraceAsString()
4316 );
4317
4318 if ( $this->isOpen() ) {
4319 // Open a new connection resource without messing with the old one
4320 $this->opened = false;
4321 $this->conn = false;
4322 $this->trxEndCallbacks = []; // don't copy
4323 $this->handleSessionLoss(); // no trx or locks anymore
4324 $this->open( $this->server, $this->user, $this->password, $this->dbName );
4325 $this->lastPing = microtime( true );
4326 }
4327 }
4328
4329 /**
4330 * Called by serialize. Throw an exception when DB connection is serialized.
4331 * This causes problems on some database engines because the connection is
4332 * not restored on unserialize.
4333 */
4334 public function __sleep() {
4335 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4336 'the connection is not restored on wakeup.' );
4337 }
4338
4339 /**
4340 * Run a few simple sanity checks and close dangling connections
4341 */
4342 public function __destruct() {
4343 if ( $this->trxLevel && $this->trxDoneWrites ) {
4344 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})." );
4345 }
4346
4347 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4348 if ( $danglingWriters ) {
4349 $fnames = implode( ', ', $danglingWriters );
4350 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
4351 }
4352
4353 if ( $this->conn ) {
4354 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4355 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4356 Wikimedia\suppressWarnings();
4357 $this->closeConnection();
4358 Wikimedia\restoreWarnings();
4359 $this->conn = false;
4360 $this->opened = false;
4361 }
4362 }
4363 }
4364
4365 class_alias( Database::class, 'DatabaseBase' ); // b/c for old name
4366 class_alias( Database::class, 'Database' ); // b/c global alias
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