3 * @defgroup Database Database
5 * This file deals with database interface functions
6 * and query specifics/optimisations.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 * http://www.gnu.org/copyleft/gpl.html
26 namespace Wikimedia\Rdbms
;
28 use Psr\Log\LoggerAwareInterface
;
29 use Psr\Log\LoggerInterface
;
30 use Wikimedia\ScopedCallback
;
31 use Wikimedia\Timestamp\ConvertibleTimestamp
;
35 use InvalidArgumentException
;
40 * Relational database abstraction object
45 abstract class Database
implements IDatabase
, IMaintainableDatabase
, LoggerAwareInterface
{
46 /** Number of times to re-try an operation in case of deadlock */
47 const DEADLOCK_TRIES
= 4;
48 /** Minimum time to wait before retry, in microseconds */
49 const DEADLOCK_DELAY_MIN
= 500000;
50 /** Maximum time to wait before retry */
51 const DEADLOCK_DELAY_MAX
= 1500000;
53 /** How long before it is worth doing a dummy query to test the connection */
55 const PING_QUERY
= 'SELECT 1 AS ping';
57 const TINY_WRITE_SEC
= 0.010;
58 const SLOW_WRITE_SEC
= 0.500;
59 const SMALL_WRITE_ROWS
= 100;
61 /** @var string SQL query */
62 protected $mLastQuery = '';
63 /** @var float|bool UNIX timestamp of last write query */
64 protected $mLastWriteTime = false;
65 /** @var string|bool */
66 protected $mPHPError = false;
75 /** @var array[] $aliases Map of (table => (dbname, schema, prefix) map) */
76 protected $tableAliases = [];
77 /** @var bool Whether this PHP instance is for a CLI script */
79 /** @var string Agent name for query profiling */
82 /** @var BagOStuff APC cache */
84 /** @var LoggerInterface */
85 protected $connLogger;
86 /** @var LoggerInterface */
87 protected $queryLogger;
88 /** @var callback Error logging callback */
89 protected $errorLogger;
91 /** @var resource|null Database connection */
92 protected $mConn = null;
94 protected $mOpened = false;
96 /** @var array[] List of (callable, method name) */
97 protected $mTrxIdleCallbacks = [];
98 /** @var array[] List of (callable, method name) */
99 protected $mTrxPreCommitCallbacks = [];
100 /** @var array[] List of (callable, method name) */
101 protected $mTrxEndCallbacks = [];
102 /** @var callable[] Map of (name => callable) */
103 protected $mTrxRecurringCallbacks = [];
104 /** @var bool Whether to suppress triggering of transaction end callbacks */
105 protected $mTrxEndCallbacksSuppressed = false;
108 protected $mTablePrefix = '';
110 protected $mSchema = '';
114 protected $mLBInfo = [];
115 /** @var bool|null */
116 protected $mDefaultBigSelects = null;
117 /** @var array|bool */
118 protected $mSchemaVars = false;
120 protected $mSessionVars = [];
121 /** @var array|null */
122 protected $preparedArgs;
123 /** @var string|bool|null Stashed value of html_errors INI setting */
124 protected $htmlErrors;
126 protected $delimiter = ';';
127 /** @var DatabaseDomain */
128 protected $currentDomain;
131 * Either 1 if a transaction is active or 0 otherwise.
132 * The other Trx fields may not be meaningfull if this is 0.
136 protected $mTrxLevel = 0;
138 * Either a short hexidecimal string if a transaction is active or ""
141 * @see Database::mTrxLevel
143 protected $mTrxShortId = '';
145 * The UNIX time that the transaction started. Callers can assume that if
146 * snapshot isolation is used, then the data is *at least* up to date to that
147 * point (possibly more up-to-date since the first SELECT defines the snapshot).
150 * @see Database::mTrxLevel
152 private $mTrxTimestamp = null;
153 /** @var float Lag estimate at the time of BEGIN */
154 private $mTrxReplicaLag = null;
156 * Remembers the function name given for starting the most recent transaction via begin().
157 * Used to provide additional context for error reporting.
160 * @see Database::mTrxLevel
162 private $mTrxFname = null;
164 * Record if possible write queries were done in the last transaction started
167 * @see Database::mTrxLevel
169 private $mTrxDoneWrites = false;
171 * Record if the current transaction was started implicitly due to DBO_TRX being set.
174 * @see Database::mTrxLevel
176 private $mTrxAutomatic = false;
178 * Array of levels of atomicity within transactions
182 private $mTrxAtomicLevels = [];
184 * Record if the current transaction was started implicitly by Database::startAtomic
188 private $mTrxAutomaticAtomic = false;
190 * Track the write query callers of the current transaction
194 private $mTrxWriteCallers = [];
196 * @var float Seconds spent in write queries for the current transaction
198 private $mTrxWriteDuration = 0.0;
200 * @var int Number of write queries for the current transaction
202 private $mTrxWriteQueryCount = 0;
204 * @var int Number of rows affected by write queries for the current transaction
206 private $mTrxWriteAffectedRows = 0;
208 * @var float Like mTrxWriteQueryCount but excludes lock-bound, easy to replicate, queries
210 private $mTrxWriteAdjDuration = 0.0;
212 * @var int Number of write queries counted in mTrxWriteAdjDuration
214 private $mTrxWriteAdjQueryCount = 0;
216 * @var float RTT time estimate
218 private $mRTTEstimate = 0.0;
220 /** @var array Map of (name => 1) for locks obtained via lock() */
221 private $mNamedLocksHeld = [];
222 /** @var array Map of (table name => 1) for TEMPORARY tables */
223 protected $mSessionTempTables = [];
225 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
226 private $lazyMasterHandle;
228 /** @var float UNIX timestamp */
229 protected $lastPing = 0.0;
231 /** @var int[] Prior mFlags values */
232 private $priorFlags = [];
234 /** @var object|string Class name or object With profileIn/profileOut methods */
236 /** @var TransactionProfiler */
237 protected $trxProfiler;
240 * Constructor and database handle and attempt to connect to the DB server
242 * IDatabase classes should not be constructed directly in external
243 * code. Database::factory() should be used instead.
245 * @param array $params Parameters passed from Database::factory()
247 function __construct( array $params ) {
248 $server = $params['host'];
249 $user = $params['user'];
250 $password = $params['password'];
251 $dbName = $params['dbname'];
253 $this->mSchema
= $params['schema'];
254 $this->mTablePrefix
= $params['tablePrefix'];
256 $this->cliMode
= $params['cliMode'];
257 // Agent name is added to SQL queries in a comment, so make sure it can't break out
258 $this->agent
= str_replace( '/', '-', $params['agent'] );
260 $this->mFlags
= $params['flags'];
261 if ( $this->mFlags
& self
::DBO_DEFAULT
) {
262 if ( $this->cliMode
) {
263 $this->mFlags
&= ~self
::DBO_TRX
;
265 $this->mFlags |
= self
::DBO_TRX
;
269 $this->mSessionVars
= $params['variables'];
271 $this->srvCache
= isset( $params['srvCache'] )
272 ?
$params['srvCache']
273 : new HashBagOStuff();
275 $this->profiler
= $params['profiler'];
276 $this->trxProfiler
= $params['trxProfiler'];
277 $this->connLogger
= $params['connLogger'];
278 $this->queryLogger
= $params['queryLogger'];
279 $this->errorLogger
= $params['errorLogger'];
281 // Set initial dummy domain until open() sets the final DB/prefix
282 $this->currentDomain
= DatabaseDomain
::newUnspecified();
285 $this->open( $server, $user, $password, $dbName );
286 } elseif ( $this->requiresDatabaseUser() ) {
287 throw new InvalidArgumentException( "No database user provided." );
290 // Set the domain object after open() sets the relevant fields
291 if ( $this->mDBname
!= '' ) {
292 // Domains with server scope but a table prefix are not used by IDatabase classes
293 $this->currentDomain
= new DatabaseDomain( $this->mDBname
, null, $this->mTablePrefix
);
298 * Construct a Database subclass instance given a database type and parameters
300 * This also connects to the database immediately upon object construction
302 * @param string $dbType A possible DB type (sqlite, mysql, postgres)
303 * @param array $p Parameter map with keys:
304 * - host : The hostname of the DB server
305 * - user : The name of the database user the client operates under
306 * - password : The password for the database user
307 * - dbname : The name of the database to use where queries do not specify one.
308 * The database must exist or an error might be thrown. Setting this to the empty string
309 * will avoid any such errors and make the handle have no implicit database scope. This is
310 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
311 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
312 * in which user names and such are defined, e.g. users are database-specific in Postgres.
313 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
314 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
315 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
316 * recognized in queries. This can be used in place of schemas for handle site farms.
317 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
318 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
319 * flag in place UNLESS this this database simply acts as a key/value store.
320 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
321 * 'mysqli' driver; the old one 'mysql' has been removed.
322 * - variables: Optional map of session variables to set after connecting. This can be
323 * used to adjust lock timeouts or encoding modes and the like.
324 * - connLogger: Optional PSR-3 logger interface instance.
325 * - queryLogger: Optional PSR-3 logger interface instance.
326 * - profiler: Optional class name or object with profileIn()/profileOut() methods.
327 * These will be called in query(), using a simplified version of the SQL that also
328 * includes the agent as a SQL comment.
329 * - trxProfiler: Optional TransactionProfiler instance.
330 * - errorLogger: Optional callback that takes an Exception and logs it.
331 * - cliMode: Whether to consider the execution context that of a CLI script.
332 * - agent: Optional name used to identify the end-user in query profiling/logging.
333 * - srvCache: Optional BagOStuff instance to an APC-style cache.
334 * @return Database|null If the database driver or extension cannot be found
335 * @throws InvalidArgumentException If the database driver or extension cannot be found
338 final public static function factory( $dbType, $p = [] ) {
339 // For database types with built-in support, the below maps type to IDatabase
340 // implementations. For types with multipe driver implementations (PHP extensions),
341 // an array can be used, keyed by extension name. In case of an array, the
342 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
343 // we auto-detect the first available driver. For types without built-in support,
344 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
345 static $builtinTypes = [
346 'mssql' => DatabaseMssql
::class,
347 'mysql' => [ 'mysqli' => DatabaseMysqli
::class ],
348 'sqlite' => DatabaseSqlite
::class,
349 'postgres' => DatabasePostgres
::class,
352 $dbType = strtolower( $dbType );
354 if ( isset( $builtinTypes[$dbType] ) ) {
355 $possibleDrivers = $builtinTypes[$dbType];
356 if ( is_string( $possibleDrivers ) ) {
357 $class = $possibleDrivers;
359 if ( !empty( $p['driver'] ) ) {
360 if ( !isset( $possibleDrivers[$p['driver']] ) ) {
361 throw new InvalidArgumentException( __METHOD__
.
362 " type '$dbType' does not support driver '{$p['driver']}'" );
364 $class = $possibleDrivers[$p['driver']];
367 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
368 if ( extension_loaded( $posDriver ) ) {
369 $class = $possibleClass;
376 $class = 'Database' . ucfirst( $dbType );
379 if ( $class === false ) {
380 throw new InvalidArgumentException( __METHOD__
.
381 " no viable database extension found for type '$dbType'" );
384 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
385 // Resolve some defaults for b/c
386 $p['host'] = isset( $p['host'] ) ?
$p['host'] : false;
387 $p['user'] = isset( $p['user'] ) ?
$p['user'] : false;
388 $p['password'] = isset( $p['password'] ) ?
$p['password'] : false;
389 $p['dbname'] = isset( $p['dbname'] ) ?
$p['dbname'] : false;
390 $p['flags'] = isset( $p['flags'] ) ?
$p['flags'] : 0;
391 $p['variables'] = isset( $p['variables'] ) ?
$p['variables'] : [];
392 $p['tablePrefix'] = isset( $p['tablePrefix'] ) ?
$p['tablePrefix'] : '';
393 $p['schema'] = isset( $p['schema'] ) ?
$p['schema'] : '';
394 $p['cliMode'] = isset( $p['cliMode'] )
396 : ( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' );
397 $p['agent'] = isset( $p['agent'] ) ?
$p['agent'] : '';
398 if ( !isset( $p['connLogger'] ) ) {
399 $p['connLogger'] = new \Psr\Log\
NullLogger();
401 if ( !isset( $p['queryLogger'] ) ) {
402 $p['queryLogger'] = new \Psr\Log\
NullLogger();
404 $p['profiler'] = isset( $p['profiler'] ) ?
$p['profiler'] : null;
405 if ( !isset( $p['trxProfiler'] ) ) {
406 $p['trxProfiler'] = new TransactionProfiler();
408 if ( !isset( $p['errorLogger'] ) ) {
409 $p['errorLogger'] = function ( Exception
$e ) {
410 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
414 $conn = new $class( $p );
423 * Set the PSR-3 logger interface to use for query logging. (The logger
424 * interfaces for connection logging and error logging can be set with the
427 * @param LoggerInterface $logger
429 public function setLogger( LoggerInterface
$logger ) {
430 $this->queryLogger
= $logger;
433 public function getServerInfo() {
434 return $this->getServerVersion();
437 public function bufferResults( $buffer = null ) {
438 $res = !$this->getFlag( self
::DBO_NOBUFFER
);
439 if ( $buffer !== null ) {
441 ?
$this->clearFlag( self
::DBO_NOBUFFER
)
442 : $this->setFlag( self
::DBO_NOBUFFER
);
449 * Turns on (false) or off (true) the automatic generation and sending
450 * of a "we're sorry, but there has been a database error" page on
451 * database errors. Default is on (false). When turned off, the
452 * code should use lastErrno() and lastError() to handle the
453 * situation as appropriate.
455 * Do not use this function outside of the Database classes.
457 * @param null|bool $ignoreErrors
458 * @return bool The previous value of the flag.
460 protected function ignoreErrors( $ignoreErrors = null ) {
461 $res = $this->getFlag( self
::DBO_IGNORE
);
462 if ( $ignoreErrors !== null ) {
463 // setFlag()/clearFlag() do not allow DBO_IGNORE changes for sanity
464 if ( $ignoreErrors ) {
465 $this->mFlags |
= self
::DBO_IGNORE
;
467 $this->mFlags
&= ~self
::DBO_IGNORE
;
474 public function trxLevel() {
475 return $this->mTrxLevel
;
478 public function trxTimestamp() {
479 return $this->mTrxLevel ?
$this->mTrxTimestamp
: null;
482 public function tablePrefix( $prefix = null ) {
483 $old = $this->mTablePrefix
;
484 if ( $prefix !== null ) {
485 $this->mTablePrefix
= $prefix;
486 $this->currentDomain
= ( $this->mDBname
!= '' )
487 ?
new DatabaseDomain( $this->mDBname
, null, $this->mTablePrefix
)
488 : DatabaseDomain
::newUnspecified();
494 public function dbSchema( $schema = null ) {
495 $old = $this->mSchema
;
496 if ( $schema !== null ) {
497 $this->mSchema
= $schema;
503 public function getLBInfo( $name = null ) {
504 if ( is_null( $name ) ) {
505 return $this->mLBInfo
;
507 if ( array_key_exists( $name, $this->mLBInfo
) ) {
508 return $this->mLBInfo
[$name];
515 public function setLBInfo( $name, $value = null ) {
516 if ( is_null( $value ) ) {
517 $this->mLBInfo
= $name;
519 $this->mLBInfo
[$name] = $value;
523 public function setLazyMasterHandle( IDatabase
$conn ) {
524 $this->lazyMasterHandle
= $conn;
528 * @return IDatabase|null
529 * @see setLazyMasterHandle()
532 protected function getLazyMasterHandle() {
533 return $this->lazyMasterHandle
;
536 public function implicitGroupby() {
540 public function implicitOrderby() {
544 public function lastQuery() {
545 return $this->mLastQuery
;
548 public function doneWrites() {
549 return (bool)$this->mLastWriteTime
;
552 public function lastDoneWrites() {
553 return $this->mLastWriteTime ?
: false;
556 public function writesPending() {
557 return $this->mTrxLevel
&& $this->mTrxDoneWrites
;
560 public function writesOrCallbacksPending() {
561 return $this->mTrxLevel
&& (
562 $this->mTrxDoneWrites ||
$this->mTrxIdleCallbacks ||
$this->mTrxPreCommitCallbacks
566 public function pendingWriteQueryDuration( $type = self
::ESTIMATE_TOTAL
) {
567 if ( !$this->mTrxLevel
) {
569 } elseif ( !$this->mTrxDoneWrites
) {
574 case self
::ESTIMATE_DB_APPLY
:
576 $rttAdjTotal = $this->mTrxWriteAdjQueryCount
* $rtt;
577 $applyTime = max( $this->mTrxWriteAdjDuration
- $rttAdjTotal, 0 );
578 // For omitted queries, make them count as something at least
579 $omitted = $this->mTrxWriteQueryCount
- $this->mTrxWriteAdjQueryCount
;
580 $applyTime +
= self
::TINY_WRITE_SEC
* $omitted;
583 default: // everything
584 return $this->mTrxWriteDuration
;
588 public function pendingWriteCallers() {
589 return $this->mTrxLevel ?
$this->mTrxWriteCallers
: [];
592 public function pendingWriteRowsAffected() {
593 return $this->mTrxWriteAffectedRows
;
597 * Get the list of method names that have pending write queries or callbacks
598 * for this transaction
602 protected function pendingWriteAndCallbackCallers() {
603 if ( !$this->mTrxLevel
) {
607 $fnames = $this->mTrxWriteCallers
;
609 $this->mTrxIdleCallbacks
,
610 $this->mTrxPreCommitCallbacks
,
611 $this->mTrxEndCallbacks
613 foreach ( $callbacks as $callback ) {
614 $fnames[] = $callback[1];
621 public function isOpen() {
622 return $this->mOpened
;
625 public function setFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
626 if ( ( $flag & self
::DBO_IGNORE
) ) {
627 throw new \
UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
630 if ( $remember === self
::REMEMBER_PRIOR
) {
631 array_push( $this->priorFlags
, $this->mFlags
);
633 $this->mFlags |
= $flag;
636 public function clearFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
637 if ( ( $flag & self
::DBO_IGNORE
) ) {
638 throw new \
UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
641 if ( $remember === self
::REMEMBER_PRIOR
) {
642 array_push( $this->priorFlags
, $this->mFlags
);
644 $this->mFlags
&= ~
$flag;
647 public function restoreFlags( $state = self
::RESTORE_PRIOR
) {
648 if ( !$this->priorFlags
) {
652 if ( $state === self
::RESTORE_INITIAL
) {
653 $this->mFlags
= reset( $this->priorFlags
);
654 $this->priorFlags
= [];
656 $this->mFlags
= array_pop( $this->priorFlags
);
660 public function getFlag( $flag ) {
661 return !!( $this->mFlags
& $flag );
665 * @param string $name Class field name
667 * @deprecated Since 1.28
669 public function getProperty( $name ) {
673 public function getDomainID() {
674 return $this->currentDomain
->getId();
677 final public function getWikiID() {
678 return $this->getDomainID();
682 * Get information about an index into an object
683 * @param string $table Table name
684 * @param string $index Index name
685 * @param string $fname Calling function name
686 * @return mixed Database-specific index description class or false if the index does not exist
688 abstract function indexInfo( $table, $index, $fname = __METHOD__
);
691 * Wrapper for addslashes()
693 * @param string $s String to be slashed.
694 * @return string Slashed string.
696 abstract function strencode( $s );
699 * Set a custom error handler for logging errors during database connection
701 protected function installErrorHandler() {
702 $this->mPHPError
= false;
703 $this->htmlErrors
= ini_set( 'html_errors', '0' );
704 set_error_handler( [ $this, 'connectionErrorLogger' ] );
708 * Restore the previous error handler and return the last PHP error for this DB
710 * @return bool|string
712 protected function restoreErrorHandler() {
713 restore_error_handler();
714 if ( $this->htmlErrors
!== false ) {
715 ini_set( 'html_errors', $this->htmlErrors
);
718 return $this->getLastPHPError();
722 * @return string|bool Last PHP error for this DB (typically connection errors)
724 protected function getLastPHPError() {
725 if ( $this->mPHPError
) {
726 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->mPHPError
);
727 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
736 * Error handler for logging errors during database connection
737 * This method should not be used outside of Database classes
740 * @param string $errstr
742 public function connectionErrorLogger( $errno, $errstr ) {
743 $this->mPHPError
= $errstr;
747 * Create a log context to pass to PSR-3 logger functions.
749 * @param array $extras Additional data to add to context
752 protected function getLogContext( array $extras = [] ) {
755 'db_server' => $this->mServer
,
756 'db_name' => $this->mDBname
,
757 'db_user' => $this->mUser
,
763 public function close() {
764 if ( $this->mConn
) {
765 if ( $this->trxLevel() ) {
766 $this->commit( __METHOD__
, self
::FLUSHING_INTERNAL
);
769 $closed = $this->closeConnection();
770 $this->mConn
= false;
772 $this->mTrxIdleCallbacks ||
773 $this->mTrxPreCommitCallbacks ||
774 $this->mTrxEndCallbacks
776 throw new RuntimeException( "Transaction callbacks still pending." );
780 $this->mOpened
= false;
786 * Make sure isOpen() returns true as a sanity check
788 * @throws DBUnexpectedError
790 protected function assertOpen() {
791 if ( !$this->isOpen() ) {
792 throw new DBUnexpectedError( $this, "DB connection was already closed." );
797 * Closes underlying database connection
799 * @return bool Whether connection was closed successfully
801 abstract protected function closeConnection();
803 public function reportConnectionError( $error = 'Unknown error' ) {
804 $myError = $this->lastError();
810 throw new DBConnectionError( $this, $error );
814 * The DBMS-dependent part of query()
816 * @param string $sql SQL query.
817 * @return ResultWrapper|bool Result object to feed to fetchObject,
818 * fetchRow, ...; or false on failure
820 abstract protected function doQuery( $sql );
823 * Determine whether a query writes to the DB.
824 * Should return true if unsure.
829 protected function isWriteQuery( $sql ) {
831 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SET|SHOW|EXPLAIN|\(SELECT)\b/i', $sql );
836 * @return string|null
838 protected function getQueryVerb( $sql ) {
839 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ?
strtoupper( $m[1] ) : null;
843 * Determine whether a SQL statement is sensitive to isolation level.
844 * A SQL statement is considered transactable if its result could vary
845 * depending on the transaction isolation level. Operational commands
846 * such as 'SET' and 'SHOW' are not considered to be transactable.
851 protected function isTransactableQuery( $sql ) {
853 $this->getQueryVerb( $sql ),
854 [ 'BEGIN', 'COMMIT', 'ROLLBACK', 'SHOW', 'SET', 'CREATE', 'ALTER' ],
860 * @param string $sql A SQL query
861 * @return bool Whether $sql is SQL for TEMPORARY table operation
863 protected function registerTempTableOperation( $sql ) {
865 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
869 $this->mSessionTempTables
[$matches[1]] = 1;
872 } elseif ( preg_match(
873 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
877 $isTemp = isset( $this->mSessionTempTables
[$matches[1]] );
878 unset( $this->mSessionTempTables
[$matches[1]] );
881 } elseif ( preg_match(
882 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
886 return isset( $this->mSessionTempTables
[$matches[1]] );
887 } elseif ( preg_match(
888 '/^(?:INSERT\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+[`"\']?(\w+)[`"\']?/i',
892 return isset( $this->mSessionTempTables
[$matches[1]] );
898 public function query( $sql, $fname = __METHOD__
, $tempIgnore = false ) {
899 $priorWritesPending = $this->writesOrCallbacksPending();
900 $this->mLastQuery
= $sql;
902 $isWrite = $this->isWriteQuery( $sql );
904 $isNonTempWrite = !$this->registerTempTableOperation( $sql );
906 $isNonTempWrite = false;
910 if ( $this->getLBInfo( 'replica' ) === true ) {
913 'Write operations are not allowed on replica database connections.'
916 # In theory, non-persistent writes are allowed in read-only mode, but due to things
917 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
918 $reason = $this->getReadOnlyReason();
919 if ( $reason !== false ) {
920 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
922 # Set a flag indicating that writes have been done
923 $this->mLastWriteTime
= microtime( true );
926 # Add trace comment to the begin of the sql string, right after the operator.
927 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
928 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
930 # Start implicit transactions that wrap the request if DBO_TRX is enabled
931 if ( !$this->mTrxLevel
&& $this->getFlag( self
::DBO_TRX
)
932 && $this->isTransactableQuery( $sql )
934 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
935 $this->mTrxAutomatic
= true;
938 # Keep track of whether the transaction has write queries pending
939 if ( $this->mTrxLevel
&& !$this->mTrxDoneWrites
&& $isWrite ) {
940 $this->mTrxDoneWrites
= true;
941 $this->trxProfiler
->transactionWritingIn(
942 $this->mServer
, $this->mDBname
, $this->mTrxShortId
);
945 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
946 $this->queryLogger
->debug( "{$this->mDBname} {$commentedSql}" );
949 # Avoid fatals if close() was called
952 # Send the query to the server
953 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
955 # Try reconnecting if the connection was lost
956 if ( false === $ret && $this->wasErrorReissuable() ) {
957 $recoverable = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
958 # Stash the last error values before anything might clear them
959 $lastError = $this->lastError();
960 $lastErrno = $this->lastErrno();
961 # Update state tracking to reflect transaction loss due to disconnection
962 $this->handleSessionLoss();
963 if ( $this->reconnect() ) {
964 $msg = __METHOD__
. ': lost connection to {dbserver}; reconnected';
965 $params = [ 'dbserver' => $this->getServer() ];
966 $this->connLogger
->warning( $msg, $params );
967 $this->queryLogger
->warning( $msg, $params +
968 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ] );
970 if ( !$recoverable ) {
971 # Callers may catch the exception and continue to use the DB
972 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname );
974 # Should be safe to silently retry the query
975 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
978 $msg = __METHOD__
. ': lost connection to {dbserver} permanently';
979 $this->connLogger
->error( $msg, [ 'dbserver' => $this->getServer() ] );
983 if ( false === $ret ) {
984 # Deadlocks cause the entire transaction to abort, not just the statement.
985 # https://dev.mysql.com/doc/refman/5.7/en/innodb-error-handling.html
986 # https://www.postgresql.org/docs/9.1/static/explicit-locking.html
987 if ( $this->wasDeadlock() ) {
988 if ( $this->explicitTrxActive() ||
$priorWritesPending ) {
989 $tempIgnore = false; // not recoverable
991 # Update state tracking to reflect transaction loss
992 $this->handleSessionLoss();
995 $this->reportQueryError(
996 $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore );
999 $res = $this->resultObject( $ret );
1005 * Helper method for query() that handles profiling and logging and sends
1006 * the query to doQuery()
1008 * @param string $sql Original SQL query
1009 * @param string $commentedSql SQL query with debugging/trace comment
1010 * @param bool $isWrite Whether the query is a (non-temporary) write operation
1011 * @param string $fname Name of the calling function
1012 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1013 * object for a successful read query, or false on failure
1015 private function doProfiledQuery( $sql, $commentedSql, $isWrite, $fname ) {
1016 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1017 # generalizeSQL() will probably cut down the query to reasonable
1018 # logging size most of the time. The substr is really just a sanity check.
1020 $queryProf = 'query-m: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1022 $queryProf = 'query: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1025 # Include query transaction state
1026 $queryProf .= $this->mTrxShortId ?
" [TRX#{$this->mTrxShortId}]" : "";
1028 $startTime = microtime( true );
1029 if ( $this->profiler
) {
1030 call_user_func( [ $this->profiler
, 'profileIn' ], $queryProf );
1032 $ret = $this->doQuery( $commentedSql );
1033 if ( $this->profiler
) {
1034 call_user_func( [ $this->profiler
, 'profileOut' ], $queryProf );
1036 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1038 unset( $queryProfSection ); // profile out (if set)
1040 if ( $ret !== false ) {
1041 $this->lastPing
= $startTime;
1042 if ( $isWrite && $this->mTrxLevel
) {
1043 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1044 $this->mTrxWriteCallers
[] = $fname;
1048 if ( $sql === self
::PING_QUERY
) {
1049 $this->mRTTEstimate
= $queryRuntime;
1052 $this->trxProfiler
->recordQueryCompletion(
1053 $queryProf, $startTime, $isWrite, $this->affectedRows()
1055 $this->queryLogger
->debug( $sql, [
1057 'master' => $isMaster,
1058 'runtime' => $queryRuntime,
1065 * Update the estimated run-time of a query, not counting large row lock times
1067 * LoadBalancer can be set to rollback transactions that will create huge replication
1068 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1069 * queries, like inserting a row can take a long time due to row locking. This method
1070 * uses some simple heuristics to discount those cases.
1072 * @param string $sql A SQL write query
1073 * @param float $runtime Total runtime, including RTT
1074 * @param int $affected Affected row count
1076 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1077 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1078 $indicativeOfReplicaRuntime = true;
1079 if ( $runtime > self
::SLOW_WRITE_SEC
) {
1080 $verb = $this->getQueryVerb( $sql );
1081 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1082 if ( $verb === 'INSERT' ) {
1083 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
;
1084 } elseif ( $verb === 'REPLACE' ) {
1085 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
/ 2;
1089 $this->mTrxWriteDuration +
= $runtime;
1090 $this->mTrxWriteQueryCount +
= 1;
1091 $this->mTrxWriteAffectedRows +
= $affected;
1092 if ( $indicativeOfReplicaRuntime ) {
1093 $this->mTrxWriteAdjDuration +
= $runtime;
1094 $this->mTrxWriteAdjQueryCount +
= 1;
1099 * Determine whether or not it is safe to retry queries after a database
1100 * connection is lost
1102 * @param string $sql SQL query
1103 * @param bool $priorWritesPending Whether there is a transaction open with
1104 * possible write queries or transaction pre-commit/idle callbacks
1105 * waiting on it to finish.
1106 * @return bool True if it is safe to retry the query, false otherwise
1108 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1109 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1110 # Dropped connections also mean that named locks are automatically released.
1111 # Only allow error suppression in autocommit mode or when the lost transaction
1112 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1113 if ( $this->mNamedLocksHeld
) {
1114 return false; // possible critical section violation
1115 } elseif ( $sql === 'COMMIT' ) {
1116 return !$priorWritesPending; // nothing written anyway? (T127428)
1117 } elseif ( $sql === 'ROLLBACK' ) {
1118 return true; // transaction lost...which is also what was requested :)
1119 } elseif ( $this->explicitTrxActive() ) {
1120 return false; // don't drop atomocity
1121 } elseif ( $priorWritesPending ) {
1122 return false; // prior writes lost from implicit transaction
1129 * Clean things up after transaction loss due to disconnection
1131 * @return null|Exception
1133 private function handleSessionLoss() {
1134 $this->mTrxLevel
= 0;
1135 $this->mTrxIdleCallbacks
= []; // T67263
1136 $this->mTrxPreCommitCallbacks
= []; // T67263
1137 $this->mSessionTempTables
= [];
1138 $this->mNamedLocksHeld
= [];
1140 // Handle callbacks in mTrxEndCallbacks
1141 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1142 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1144 } catch ( Exception
$e ) {
1145 // Already logged; move on...
1151 * Checks whether the cause of the error is detected to be a timeout.
1153 * It returns false by default, and not all engines support detecting this yet.
1154 * If this returns false, it will be treated as a generic query error.
1156 * @param string $error Error text
1157 * @param int $errno Error number
1160 protected function wasQueryTimeout( $error, $errno ) {
1164 public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
1165 if ( $this->ignoreErrors() ||
$tempIgnore ) {
1166 $this->queryLogger
->debug( "SQL ERROR (ignored): $error\n" );
1168 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1169 $this->queryLogger
->error(
1170 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1171 $this->getLogContext( [
1172 'method' => __METHOD__
,
1175 'sql1line' => $sql1line,
1179 $this->queryLogger
->debug( "SQL ERROR: " . $error . "\n" );
1180 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1181 if ( $wasQueryTimeout ) {
1182 throw new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1184 throw new DBQueryError( $this, $error, $errno, $sql, $fname );
1189 public function freeResult( $res ) {
1192 public function selectField(
1193 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1195 if ( $var === '*' ) { // sanity
1196 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1199 if ( !is_array( $options ) ) {
1200 $options = [ $options ];
1203 $options['LIMIT'] = 1;
1205 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1206 if ( $res === false ||
!$this->numRows( $res ) ) {
1210 $row = $this->fetchRow( $res );
1212 if ( $row !== false ) {
1213 return reset( $row );
1219 public function selectFieldValues(
1220 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1222 if ( $var === '*' ) { // sanity
1223 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1224 } elseif ( !is_string( $var ) ) { // sanity
1225 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1228 if ( !is_array( $options ) ) {
1229 $options = [ $options ];
1232 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1233 if ( $res === false ) {
1238 foreach ( $res as $row ) {
1239 $values[] = $row->$var;
1246 * Returns an optional USE INDEX clause to go after the table, and a
1247 * string to go at the end of the query.
1249 * @param array $options Associative array of options to be turned into
1250 * an SQL query, valid keys are listed in the function.
1252 * @see Database::select()
1254 protected function makeSelectOptions( $options ) {
1255 $preLimitTail = $postLimitTail = '';
1260 foreach ( $options as $key => $option ) {
1261 if ( is_numeric( $key ) ) {
1262 $noKeyOptions[$option] = true;
1266 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1268 $preLimitTail .= $this->makeOrderBy( $options );
1270 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1271 $postLimitTail .= ' FOR UPDATE';
1274 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1275 $postLimitTail .= ' LOCK IN SHARE MODE';
1278 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1279 $startOpts .= 'DISTINCT';
1282 # Various MySQL extensions
1283 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1284 $startOpts .= ' /*! STRAIGHT_JOIN */';
1287 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1288 $startOpts .= ' HIGH_PRIORITY';
1291 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1292 $startOpts .= ' SQL_BIG_RESULT';
1295 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1296 $startOpts .= ' SQL_BUFFER_RESULT';
1299 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1300 $startOpts .= ' SQL_SMALL_RESULT';
1303 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1304 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1307 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1308 $startOpts .= ' SQL_CACHE';
1311 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1312 $startOpts .= ' SQL_NO_CACHE';
1315 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1316 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1320 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1321 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1326 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1330 * Returns an optional GROUP BY with an optional HAVING
1332 * @param array $options Associative array of options
1334 * @see Database::select()
1337 protected function makeGroupByWithHaving( $options ) {
1339 if ( isset( $options['GROUP BY'] ) ) {
1340 $gb = is_array( $options['GROUP BY'] )
1341 ?
implode( ',', $options['GROUP BY'] )
1342 : $options['GROUP BY'];
1343 $sql .= ' GROUP BY ' . $gb;
1345 if ( isset( $options['HAVING'] ) ) {
1346 $having = is_array( $options['HAVING'] )
1347 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1348 : $options['HAVING'];
1349 $sql .= ' HAVING ' . $having;
1356 * Returns an optional ORDER BY
1358 * @param array $options Associative array of options
1360 * @see Database::select()
1363 protected function makeOrderBy( $options ) {
1364 if ( isset( $options['ORDER BY'] ) ) {
1365 $ob = is_array( $options['ORDER BY'] )
1366 ?
implode( ',', $options['ORDER BY'] )
1367 : $options['ORDER BY'];
1369 return ' ORDER BY ' . $ob;
1375 public function select( $table, $vars, $conds = '', $fname = __METHOD__
,
1376 $options = [], $join_conds = [] ) {
1377 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1379 return $this->query( $sql, $fname );
1382 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1383 $options = [], $join_conds = []
1385 if ( is_array( $vars ) ) {
1386 $vars = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1389 $options = (array)$options;
1390 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1391 ?
$options['USE INDEX']
1394 isset( $options['IGNORE INDEX'] ) &&
1395 is_array( $options['IGNORE INDEX'] )
1397 ?
$options['IGNORE INDEX']
1400 if ( is_array( $table ) ) {
1402 $this->tableNamesWithIndexClauseOrJOIN(
1403 $table, $useIndexes, $ignoreIndexes, $join_conds );
1404 } elseif ( $table != '' ) {
1405 if ( $table[0] == ' ' ) {
1406 $from = ' FROM ' . $table;
1409 $this->tableNamesWithIndexClauseOrJOIN(
1410 [ $table ], $useIndexes, $ignoreIndexes, [] );
1416 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1417 $this->makeSelectOptions( $options );
1419 if ( !empty( $conds ) ) {
1420 if ( is_array( $conds ) ) {
1421 $conds = $this->makeList( $conds, self
::LIST_AND
);
1423 $sql = "SELECT $startOpts $vars $from $useIndex $ignoreIndex " .
1424 "WHERE $conds $preLimitTail";
1426 $sql = "SELECT $startOpts $vars $from $useIndex $ignoreIndex $preLimitTail";
1429 if ( isset( $options['LIMIT'] ) ) {
1430 $sql = $this->limitResult( $sql, $options['LIMIT'],
1431 isset( $options['OFFSET'] ) ?
$options['OFFSET'] : false );
1433 $sql = "$sql $postLimitTail";
1435 if ( isset( $options['EXPLAIN'] ) ) {
1436 $sql = 'EXPLAIN ' . $sql;
1442 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1443 $options = [], $join_conds = []
1445 $options = (array)$options;
1446 $options['LIMIT'] = 1;
1447 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1449 if ( $res === false ) {
1453 if ( !$this->numRows( $res ) ) {
1457 $obj = $this->fetchObject( $res );
1462 public function estimateRowCount(
1463 $table, $vars = '*', $conds = '', $fname = __METHOD__
, $options = []
1466 $res = $this->select( $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options );
1469 $row = $this->fetchRow( $res );
1470 $rows = ( isset( $row['rowcount'] ) ) ?
(int)$row['rowcount'] : 0;
1476 public function selectRowCount(
1477 $tables, $vars = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1480 $sql = $this->selectSQLText( $tables, '1', $conds, $fname, $options, $join_conds );
1481 // The identifier quotes is primarily for MSSQL.
1482 $rowCountCol = $this->addIdentifierQuotes( "rowcount" );
1483 $tableName = $this->addIdentifierQuotes( "tmp_count" );
1484 $res = $this->query( "SELECT COUNT(*) AS $rowCountCol FROM ($sql) $tableName", $fname );
1487 $row = $this->fetchRow( $res );
1488 $rows = ( isset( $row['rowcount'] ) ) ?
(int)$row['rowcount'] : 0;
1495 * Removes most variables from an SQL query and replaces them with X or N for numbers.
1496 * It's only slightly flawed. Don't use for anything important.
1498 * @param string $sql A SQL Query
1502 protected static function generalizeSQL( $sql ) {
1503 # This does the same as the regexp below would do, but in such a way
1504 # as to avoid crashing php on some large strings.
1505 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
1507 $sql = str_replace( "\\\\", '', $sql );
1508 $sql = str_replace( "\\'", '', $sql );
1509 $sql = str_replace( "\\\"", '', $sql );
1510 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
1511 $sql = preg_replace( '/".*"/s', "'X'", $sql );
1513 # All newlines, tabs, etc replaced by single space
1514 $sql = preg_replace( '/\s+/', ' ', $sql );
1517 # except the ones surrounded by characters, e.g. l10n
1518 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
1519 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
1524 public function fieldExists( $table, $field, $fname = __METHOD__
) {
1525 $info = $this->fieldInfo( $table, $field );
1530 public function indexExists( $table, $index, $fname = __METHOD__
) {
1531 if ( !$this->tableExists( $table ) ) {
1535 $info = $this->indexInfo( $table, $index, $fname );
1536 if ( is_null( $info ) ) {
1539 return $info !== false;
1543 public function tableExists( $table, $fname = __METHOD__
) {
1544 $tableRaw = $this->tableName( $table, 'raw' );
1545 if ( isset( $this->mSessionTempTables
[$tableRaw] ) ) {
1546 return true; // already known to exist
1549 $table = $this->tableName( $table );
1550 $ignoreErrors = true;
1551 $res = $this->query( "SELECT 1 FROM $table LIMIT 1", $fname, $ignoreErrors );
1556 public function indexUnique( $table, $index ) {
1557 $indexInfo = $this->indexInfo( $table, $index );
1559 if ( !$indexInfo ) {
1563 return !$indexInfo[0]->Non_unique
;
1567 * Helper for Database::insert().
1569 * @param array $options
1572 protected function makeInsertOptions( $options ) {
1573 return implode( ' ', $options );
1576 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
1577 # No rows to insert, easy just return now
1578 if ( !count( $a ) ) {
1582 $table = $this->tableName( $table );
1584 if ( !is_array( $options ) ) {
1585 $options = [ $options ];
1589 if ( isset( $options['fileHandle'] ) ) {
1590 $fh = $options['fileHandle'];
1592 $options = $this->makeInsertOptions( $options );
1594 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1596 $keys = array_keys( $a[0] );
1599 $keys = array_keys( $a );
1602 $sql = 'INSERT ' . $options .
1603 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1607 foreach ( $a as $row ) {
1613 $sql .= '(' . $this->makeList( $row ) . ')';
1616 $sql .= '(' . $this->makeList( $a ) . ')';
1619 if ( $fh !== null && false === fwrite( $fh, $sql ) ) {
1621 } elseif ( $fh !== null ) {
1625 return (bool)$this->query( $sql, $fname );
1629 * Make UPDATE options array for Database::makeUpdateOptions
1631 * @param array $options
1634 protected function makeUpdateOptionsArray( $options ) {
1635 if ( !is_array( $options ) ) {
1636 $options = [ $options ];
1641 if ( in_array( 'IGNORE', $options ) ) {
1649 * Make UPDATE options for the Database::update function
1651 * @param array $options The options passed to Database::update
1654 protected function makeUpdateOptions( $options ) {
1655 $opts = $this->makeUpdateOptionsArray( $options );
1657 return implode( ' ', $opts );
1660 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
1661 $table = $this->tableName( $table );
1662 $opts = $this->makeUpdateOptions( $options );
1663 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
1665 if ( $conds !== [] && $conds !== '*' ) {
1666 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
1669 return (bool)$this->query( $sql, $fname );
1672 public function makeList( $a, $mode = self
::LIST_COMMA
) {
1673 if ( !is_array( $a ) ) {
1674 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1680 foreach ( $a as $field => $value ) {
1682 if ( $mode == self
::LIST_AND
) {
1684 } elseif ( $mode == self
::LIST_OR
) {
1693 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
1694 $list .= "($value)";
1695 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
1698 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
1700 // Remove null from array to be handled separately if found
1701 $includeNull = false;
1702 foreach ( array_keys( $value, null, true ) as $nullKey ) {
1703 $includeNull = true;
1704 unset( $value[$nullKey] );
1706 if ( count( $value ) == 0 && !$includeNull ) {
1707 throw new InvalidArgumentException(
1708 __METHOD__
. ": empty input for field $field" );
1709 } elseif ( count( $value ) == 0 ) {
1710 // only check if $field is null
1711 $list .= "$field IS NULL";
1713 // IN clause contains at least one valid element
1714 if ( $includeNull ) {
1715 // Group subconditions to ensure correct precedence
1718 if ( count( $value ) == 1 ) {
1719 // Special-case single values, as IN isn't terribly efficient
1720 // Don't necessarily assume the single key is 0; we don't
1721 // enforce linear numeric ordering on other arrays here.
1722 $value = array_values( $value )[0];
1723 $list .= $field . " = " . $this->addQuotes( $value );
1725 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
1727 // if null present in array, append IS NULL
1728 if ( $includeNull ) {
1729 $list .= " OR $field IS NULL)";
1732 } elseif ( $value === null ) {
1733 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
1734 $list .= "$field IS ";
1735 } elseif ( $mode == self
::LIST_SET
) {
1736 $list .= "$field = ";
1741 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
1743 $list .= "$field = ";
1745 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
1752 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
1755 foreach ( $data as $base => $sub ) {
1756 if ( count( $sub ) ) {
1757 $conds[] = $this->makeList(
1758 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
1764 return $this->makeList( $conds, self
::LIST_OR
);
1766 // Nothing to search for...
1771 public function aggregateValue( $valuedata, $valuename = 'value' ) {
1775 public function bitNot( $field ) {
1779 public function bitAnd( $fieldLeft, $fieldRight ) {
1780 return "($fieldLeft & $fieldRight)";
1783 public function bitOr( $fieldLeft, $fieldRight ) {
1784 return "($fieldLeft | $fieldRight)";
1787 public function buildConcat( $stringList ) {
1788 return 'CONCAT(' . implode( ',', $stringList ) . ')';
1791 public function buildGroupConcatField(
1792 $delim, $table, $field, $conds = '', $join_conds = []
1794 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
1796 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
1799 public function buildStringCast( $field ) {
1803 public function databasesAreIndependent() {
1807 public function selectDB( $db ) {
1808 # Stub. Shouldn't cause serious problems if it's not overridden, but
1809 # if your database engine supports a concept similar to MySQL's
1810 # databases you may as well.
1811 $this->mDBname
= $db;
1816 public function getDBname() {
1817 return $this->mDBname
;
1820 public function getServer() {
1821 return $this->mServer
;
1824 public function tableName( $name, $format = 'quoted' ) {
1825 # Skip the entire process when we have a string quoted on both ends.
1826 # Note that we check the end so that we will still quote any use of
1827 # use of `database`.table. But won't break things if someone wants
1828 # to query a database table with a dot in the name.
1829 if ( $this->isQuotedIdentifier( $name ) ) {
1833 # Lets test for any bits of text that should never show up in a table
1834 # name. Basically anything like JOIN or ON which are actually part of
1835 # SQL queries, but may end up inside of the table value to combine
1836 # sql. Such as how the API is doing.
1837 # Note that we use a whitespace test rather than a \b test to avoid
1838 # any remote case where a word like on may be inside of a table name
1839 # surrounded by symbols which may be considered word breaks.
1840 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
1844 # Split database and table into proper variables.
1845 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
1847 # Quote $table and apply the prefix if not quoted.
1848 # $tableName might be empty if this is called from Database::replaceVars()
1849 $tableName = "{$prefix}{$table}";
1850 if ( $format === 'quoted'
1851 && !$this->isQuotedIdentifier( $tableName )
1852 && $tableName !== ''
1854 $tableName = $this->addIdentifierQuotes( $tableName );
1857 # Quote $schema and $database and merge them with the table name if needed
1858 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
1859 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
1865 * Get the table components needed for a query given the currently selected database
1867 * @param string $name Table name in the form of db.schema.table, db.table, or table
1868 * @return array (DB name or "" for default, schema name, table prefix, table name)
1870 protected function qualifiedTableComponents( $name ) {
1871 # We reverse the explode so that database.table and table both output the correct table.
1872 $dbDetails = explode( '.', $name, 3 );
1873 if ( count( $dbDetails ) == 3 ) {
1874 list( $database, $schema, $table ) = $dbDetails;
1875 # We don't want any prefix added in this case
1877 } elseif ( count( $dbDetails ) == 2 ) {
1878 list( $database, $table ) = $dbDetails;
1879 # We don't want any prefix added in this case
1881 # In dbs that support it, $database may actually be the schema
1882 # but that doesn't affect any of the functionality here
1885 list( $table ) = $dbDetails;
1886 if ( isset( $this->tableAliases
[$table] ) ) {
1887 $database = $this->tableAliases
[$table]['dbname'];
1888 $schema = is_string( $this->tableAliases
[$table]['schema'] )
1889 ?
$this->tableAliases
[$table]['schema']
1891 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
1892 ?
$this->tableAliases
[$table]['prefix']
1893 : $this->mTablePrefix
;
1896 $schema = $this->mSchema
; # Default schema
1897 $prefix = $this->mTablePrefix
; # Default prefix
1901 return [ $database, $schema, $prefix, $table ];
1905 * @param string|null $namespace Database or schema
1906 * @param string $relation Name of table, view, sequence, etc...
1907 * @param string $format One of (raw, quoted)
1908 * @return string Relation name with quoted and merged $namespace as needed
1910 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
1911 if ( strlen( $namespace ) ) {
1912 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
1913 $namespace = $this->addIdentifierQuotes( $namespace );
1915 $relation = $namespace . '.' . $relation;
1921 public function tableNames() {
1922 $inArray = func_get_args();
1925 foreach ( $inArray as $name ) {
1926 $retVal[$name] = $this->tableName( $name );
1932 public function tableNamesN() {
1933 $inArray = func_get_args();
1936 foreach ( $inArray as $name ) {
1937 $retVal[] = $this->tableName( $name );
1944 * Get an aliased table name
1945 * e.g. tableName AS newTableName
1947 * @param string $name Table name, see tableName()
1948 * @param string|bool $alias Alias (optional)
1949 * @return string SQL name for aliased table. Will not alias a table to its own name
1951 protected function tableNameWithAlias( $name, $alias = false ) {
1952 if ( !$alias ||
$alias == $name ) {
1953 return $this->tableName( $name );
1955 return $this->tableName( $name ) . ' ' . $this->addIdentifierQuotes( $alias );
1960 * Gets an array of aliased table names
1962 * @param array $tables [ [alias] => table ]
1963 * @return string[] See tableNameWithAlias()
1965 protected function tableNamesWithAlias( $tables ) {
1967 foreach ( $tables as $alias => $table ) {
1968 if ( is_numeric( $alias ) ) {
1971 $retval[] = $this->tableNameWithAlias( $table, $alias );
1978 * Get an aliased field name
1979 * e.g. fieldName AS newFieldName
1981 * @param string $name Field name
1982 * @param string|bool $alias Alias (optional)
1983 * @return string SQL name for aliased field. Will not alias a field to its own name
1985 protected function fieldNameWithAlias( $name, $alias = false ) {
1986 if ( !$alias ||
(string)$alias === (string)$name ) {
1989 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
1994 * Gets an array of aliased field names
1996 * @param array $fields [ [alias] => field ]
1997 * @return string[] See fieldNameWithAlias()
1999 protected function fieldNamesWithAlias( $fields ) {
2001 foreach ( $fields as $alias => $field ) {
2002 if ( is_numeric( $alias ) ) {
2005 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2012 * Get the aliased table name clause for a FROM clause
2013 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2015 * @param array $tables ( [alias] => table )
2016 * @param array $use_index Same as for select()
2017 * @param array $ignore_index Same as for select()
2018 * @param array $join_conds Same as for select()
2021 protected function tableNamesWithIndexClauseOrJOIN(
2022 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2026 $use_index = (array)$use_index;
2027 $ignore_index = (array)$ignore_index;
2028 $join_conds = (array)$join_conds;
2030 foreach ( $tables as $alias => $table ) {
2031 if ( !is_string( $alias ) ) {
2032 // No alias? Set it equal to the table name
2036 if ( is_array( $table ) ) {
2037 // A parenthesized group
2038 if ( count( $table ) > 1 ) {
2040 . $this->tableNamesWithIndexClauseOrJOIN( $table, $use_index, $ignore_index, $join_conds )
2044 $innerTable = reset( $table );
2045 $innerAlias = key( $table );
2046 $joinedTable = $this->tableNameWithAlias(
2048 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2052 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2055 // Is there a JOIN clause for this table?
2056 if ( isset( $join_conds[$alias] ) ) {
2057 list( $joinType, $conds ) = $join_conds[$alias];
2058 $tableClause = $joinType;
2059 $tableClause .= ' ' . $joinedTable;
2060 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2061 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2063 $tableClause .= ' ' . $use;
2066 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2067 $ignore = $this->ignoreIndexClause(
2068 implode( ',', (array)$ignore_index[$alias] ) );
2069 if ( $ignore != '' ) {
2070 $tableClause .= ' ' . $ignore;
2073 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2075 $tableClause .= ' ON (' . $on . ')';
2078 $retJOIN[] = $tableClause;
2079 } elseif ( isset( $use_index[$alias] ) ) {
2080 // Is there an INDEX clause for this table?
2081 $tableClause = $joinedTable;
2082 $tableClause .= ' ' . $this->useIndexClause(
2083 implode( ',', (array)$use_index[$alias] )
2086 $ret[] = $tableClause;
2087 } elseif ( isset( $ignore_index[$alias] ) ) {
2088 // Is there an INDEX clause for this table?
2089 $tableClause = $joinedTable;
2090 $tableClause .= ' ' . $this->ignoreIndexClause(
2091 implode( ',', (array)$ignore_index[$alias] )
2094 $ret[] = $tableClause;
2096 $tableClause = $joinedTable;
2098 $ret[] = $tableClause;
2102 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2103 $implicitJoins = !empty( $ret ) ?
implode( ',', $ret ) : "";
2104 $explicitJoins = !empty( $retJOIN ) ?
implode( ' ', $retJOIN ) : "";
2106 // Compile our final table clause
2107 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2111 * Allows for index remapping in queries where this is not consistent across DBMS
2113 * @param string $index
2116 protected function indexName( $index ) {
2120 public function addQuotes( $s ) {
2121 if ( $s instanceof Blob
) {
2124 if ( $s === null ) {
2126 } elseif ( is_bool( $s ) ) {
2129 # This will also quote numeric values. This should be harmless,
2130 # and protects against weird problems that occur when they really
2131 # _are_ strings such as article titles and string->number->string
2132 # conversion is not 1:1.
2133 return "'" . $this->strencode( $s ) . "'";
2138 * Quotes an identifier using `backticks` or "double quotes" depending on the database type.
2139 * MySQL uses `backticks` while basically everything else uses double quotes.
2140 * Since MySQL is the odd one out here the double quotes are our generic
2141 * and we implement backticks in DatabaseMysqlBase.
2146 public function addIdentifierQuotes( $s ) {
2147 return '"' . str_replace( '"', '""', $s ) . '"';
2151 * Returns if the given identifier looks quoted or not according to
2152 * the database convention for quoting identifiers .
2154 * @note Do not use this to determine if untrusted input is safe.
2155 * A malicious user can trick this function.
2156 * @param string $name
2159 public function isQuotedIdentifier( $name ) {
2160 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2165 * @param string $escapeChar
2168 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2169 return str_replace( [ $escapeChar, '%', '_' ],
2170 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2174 public function buildLike() {
2175 $params = func_get_args();
2177 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2178 $params = $params[0];
2183 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2184 // may escape backslashes, creating problems of double escaping. The `
2185 // character has good cross-DBMS compatibility, avoiding special operators
2186 // in MS SQL like ^ and %
2189 foreach ( $params as $value ) {
2190 if ( $value instanceof LikeMatch
) {
2191 $s .= $value->toString();
2193 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2197 return ' LIKE ' . $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2200 public function anyChar() {
2201 return new LikeMatch( '_' );
2204 public function anyString() {
2205 return new LikeMatch( '%' );
2208 public function nextSequenceValue( $seqName ) {
2213 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2214 * is only needed because a) MySQL must be as efficient as possible due to
2215 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2216 * which index to pick. Anyway, other databases might have different
2217 * indexes on a given table. So don't bother overriding this unless you're
2219 * @param string $index
2222 public function useIndexClause( $index ) {
2227 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2228 * is only needed because a) MySQL must be as efficient as possible due to
2229 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2230 * which index to pick. Anyway, other databases might have different
2231 * indexes on a given table. So don't bother overriding this unless you're
2233 * @param string $index
2236 public function ignoreIndexClause( $index ) {
2240 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2241 $quotedTable = $this->tableName( $table );
2243 if ( count( $rows ) == 0 ) {
2248 if ( !is_array( reset( $rows ) ) ) {
2252 // @FXIME: this is not atomic, but a trx would break affectedRows()
2253 foreach ( $rows as $row ) {
2254 # Delete rows which collide
2255 if ( $uniqueIndexes ) {
2256 $sql = "DELETE FROM $quotedTable WHERE ";
2258 foreach ( $uniqueIndexes as $index ) {
2265 if ( is_array( $index ) ) {
2267 foreach ( $index as $col ) {
2273 $sql .= $col . '=' . $this->addQuotes( $row[$col] );
2276 $sql .= $index . '=' . $this->addQuotes( $row[$index] );
2280 $this->query( $sql, $fname );
2283 # Now insert the row
2284 $this->insert( $table, $row, $fname );
2289 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2292 * @param string $table Table name
2293 * @param array|string $rows Row(s) to insert
2294 * @param string $fname Caller function name
2296 * @return ResultWrapper
2298 protected function nativeReplace( $table, $rows, $fname ) {
2299 $table = $this->tableName( $table );
2302 if ( !is_array( reset( $rows ) ) ) {
2306 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2309 foreach ( $rows as $row ) {
2316 $sql .= '(' . $this->makeList( $row ) . ')';
2319 return $this->query( $sql, $fname );
2322 public function upsert( $table, array $rows, array $uniqueIndexes, array $set,
2325 if ( !count( $rows ) ) {
2326 return true; // nothing to do
2329 if ( !is_array( reset( $rows ) ) ) {
2333 if ( count( $uniqueIndexes ) ) {
2334 $clauses = []; // list WHERE clauses that each identify a single row
2335 foreach ( $rows as $row ) {
2336 foreach ( $uniqueIndexes as $index ) {
2337 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2338 $rowKey = []; // unique key to this row
2339 foreach ( $index as $column ) {
2340 $rowKey[$column] = $row[$column];
2342 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2345 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2350 $useTrx = !$this->mTrxLevel
;
2352 $this->begin( $fname, self
::TRANSACTION_INTERNAL
);
2355 # Update any existing conflicting row(s)
2356 if ( $where !== false ) {
2357 $ok = $this->update( $table, $set, $where, $fname );
2361 # Now insert any non-conflicting row(s)
2362 $ok = $this->insert( $table, $rows, $fname, [ 'IGNORE' ] ) && $ok;
2363 } catch ( Exception
$e ) {
2365 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
2370 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
2376 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2380 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2383 $delTable = $this->tableName( $delTable );
2384 $joinTable = $this->tableName( $joinTable );
2385 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2386 if ( $conds != '*' ) {
2387 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2391 $this->query( $sql, $fname );
2394 public function textFieldSize( $table, $field ) {
2395 $table = $this->tableName( $table );
2396 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
2397 $res = $this->query( $sql, __METHOD__
);
2398 $row = $this->fetchObject( $res );
2402 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
2411 public function delete( $table, $conds, $fname = __METHOD__
) {
2413 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
2416 $table = $this->tableName( $table );
2417 $sql = "DELETE FROM $table";
2419 if ( $conds != '*' ) {
2420 if ( is_array( $conds ) ) {
2421 $conds = $this->makeList( $conds, self
::LIST_AND
);
2423 $sql .= ' WHERE ' . $conds;
2426 return $this->query( $sql, $fname );
2429 public function insertSelect(
2430 $destTable, $srcTable, $varMap, $conds,
2431 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2433 if ( $this->cliMode
) {
2434 // For massive migrations with downtime, we don't want to select everything
2435 // into memory and OOM, so do all this native on the server side if possible.
2436 return $this->nativeInsertSelect(
2448 return $this->nonNativeInsertSelect(
2461 * Implementation of insertSelect() based on select() and insert()
2463 * @see IDatabase::insertSelect()
2465 * @param string $destTable
2466 * @param string|array $srcTable
2467 * @param array $varMap
2468 * @param array $conds
2469 * @param string $fname
2470 * @param array $insertOptions
2471 * @param array $selectOptions
2472 * @param array $selectJoinConds
2475 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
2476 $fname = __METHOD__
,
2477 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2479 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
2480 // on only the master (without needing row-based-replication). It also makes it easy to
2481 // know how big the INSERT is going to be.
2483 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
2484 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
2486 $selectOptions[] = 'FOR UPDATE';
2487 $res = $this->select(
2488 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
2495 foreach ( $res as $row ) {
2496 $rows[] = (array)$row;
2499 return $this->insert( $destTable, $rows, $fname, $insertOptions );
2503 * Native server-side implementation of insertSelect() for situations where
2504 * we don't want to select everything into memory
2506 * @see IDatabase::insertSelect()
2507 * @param string $destTable
2508 * @param string|array $srcTable
2509 * @param array $varMap
2510 * @param array $conds
2511 * @param string $fname
2512 * @param array $insertOptions
2513 * @param array $selectOptions
2514 * @param array $selectJoinConds
2517 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
2518 $fname = __METHOD__
,
2519 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2521 $destTable = $this->tableName( $destTable );
2523 if ( !is_array( $insertOptions ) ) {
2524 $insertOptions = [ $insertOptions ];
2527 $insertOptions = $this->makeInsertOptions( $insertOptions );
2529 $selectSql = $this->selectSQLText(
2531 array_values( $varMap ),
2538 $sql = "INSERT $insertOptions" .
2539 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
2542 return $this->query( $sql, $fname );
2546 * Construct a LIMIT query with optional offset. This is used for query
2547 * pages. The SQL should be adjusted so that only the first $limit rows
2548 * are returned. If $offset is provided as well, then the first $offset
2549 * rows should be discarded, and the next $limit rows should be returned.
2550 * If the result of the query is not ordered, then the rows to be returned
2551 * are theoretically arbitrary.
2553 * $sql is expected to be a SELECT, if that makes a difference.
2555 * The version provided by default works in MySQL and SQLite. It will very
2556 * likely need to be overridden for most other DBMSes.
2558 * @param string $sql SQL query we will append the limit too
2559 * @param int $limit The SQL limit
2560 * @param int|bool $offset The SQL offset (default false)
2561 * @throws DBUnexpectedError
2564 public function limitResult( $sql, $limit, $offset = false ) {
2565 if ( !is_numeric( $limit ) ) {
2566 throw new DBUnexpectedError( $this,
2567 "Invalid non-numeric limit passed to limitResult()\n" );
2570 return "$sql LIMIT "
2571 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
2575 public function unionSupportsOrderAndLimit() {
2576 return true; // True for almost every DB supported
2579 public function unionQueries( $sqls, $all ) {
2580 $glue = $all ?
') UNION ALL (' : ') UNION (';
2582 return '(' . implode( $glue, $sqls ) . ')';
2585 public function unionConditionPermutations(
2586 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
2587 $options = [], $join_conds = []
2589 // First, build the Cartesian product of $permute_conds
2591 foreach ( $permute_conds as $field => $values ) {
2593 // Skip empty $values
2596 $values = array_unique( $values ); // For sanity
2598 foreach ( $conds as $cond ) {
2599 foreach ( $values as $value ) {
2600 $cond[$field] = $value;
2601 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
2607 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
2609 // If there's just one condition and no subordering, hand off to
2610 // selectSQLText directly.
2611 if ( count( $conds ) === 1 &&
2612 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
2614 return $this->selectSQLText(
2615 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
2619 // Otherwise, we need to pull out the order and limit to apply after
2620 // the union. Then build the SQL queries for each set of conditions in
2621 // $conds. Then union them together (using UNION ALL, because the
2622 // product *should* already be distinct).
2623 $orderBy = $this->makeOrderBy( $options );
2624 $limit = isset( $options['LIMIT'] ) ?
$options['LIMIT'] : null;
2625 $offset = isset( $options['OFFSET'] ) ?
$options['OFFSET'] : false;
2626 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
2627 if ( !$this->unionSupportsOrderAndLimit() ) {
2628 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
2630 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
2631 $options['ORDER BY'] = $options['INNER ORDER BY'];
2633 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
2634 // We need to increase the limit by the offset rather than
2635 // using the offset directly, otherwise it'll skip incorrectly
2636 // in the subqueries.
2637 $options['LIMIT'] = $limit +
$offset;
2638 unset( $options['OFFSET'] );
2643 foreach ( $conds as $cond ) {
2644 $sqls[] = $this->selectSQLText(
2645 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
2648 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
2649 if ( $limit !== null ) {
2650 $sql = $this->limitResult( $sql, $limit, $offset );
2656 public function conditional( $cond, $trueVal, $falseVal ) {
2657 if ( is_array( $cond ) ) {
2658 $cond = $this->makeList( $cond, self
::LIST_AND
);
2661 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
2664 public function strreplace( $orig, $old, $new ) {
2665 return "REPLACE({$orig}, {$old}, {$new})";
2668 public function getServerUptime() {
2672 public function wasDeadlock() {
2676 public function wasLockTimeout() {
2680 public function wasErrorReissuable() {
2684 public function wasReadOnlyError() {
2689 * Do not use this method outside of Database/DBError classes
2691 * @param int|string $errno
2692 * @return bool Whether the given query error was a connection drop
2694 public function wasConnectionError( $errno ) {
2698 public function deadlockLoop() {
2699 $args = func_get_args();
2700 $function = array_shift( $args );
2701 $tries = self
::DEADLOCK_TRIES
;
2703 $this->begin( __METHOD__
);
2706 /** @var Exception $e */
2710 $retVal = call_user_func_array( $function, $args );
2712 } catch ( DBQueryError
$e ) {
2713 if ( $this->wasDeadlock() ) {
2714 // Retry after a randomized delay
2715 usleep( mt_rand( self
::DEADLOCK_DELAY_MIN
, self
::DEADLOCK_DELAY_MAX
) );
2717 // Throw the error back up
2721 } while ( --$tries > 0 );
2723 if ( $tries <= 0 ) {
2724 // Too many deadlocks; give up
2725 $this->rollback( __METHOD__
);
2728 $this->commit( __METHOD__
);
2734 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
2735 # Real waits are implemented in the subclass.
2739 public function getReplicaPos() {
2744 public function getMasterPos() {
2749 public function serverIsReadOnly() {
2753 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
2754 if ( !$this->mTrxLevel
) {
2755 throw new DBUnexpectedError( $this, "No transaction is active." );
2757 $this->mTrxEndCallbacks
[] = [ $callback, $fname ];
2760 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
2761 $this->mTrxIdleCallbacks
[] = [ $callback, $fname ];
2762 if ( !$this->mTrxLevel
) {
2763 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
2767 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
2768 if ( $this->mTrxLevel ||
$this->getFlag( self
::DBO_TRX
) ) {
2769 // As long as DBO_TRX is set, writes will accumulate until the load balancer issues
2770 // an implicit commit of all peer databases. This is true even if a transaction has
2771 // not yet been triggered by writes; make sure $callback runs *after* any such writes.
2772 $this->mTrxPreCommitCallbacks
[] = [ $callback, $fname ];
2774 // No transaction is active nor will start implicitly, so make one for this callback
2775 $this->startAtomic( __METHOD__
);
2777 call_user_func( $callback );
2778 $this->endAtomic( __METHOD__
);
2779 } catch ( Exception
$e ) {
2780 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
2786 final public function setTransactionListener( $name, callable
$callback = null ) {
2788 $this->mTrxRecurringCallbacks
[$name] = $callback;
2790 unset( $this->mTrxRecurringCallbacks
[$name] );
2795 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
2797 * This method should not be used outside of Database/LoadBalancer
2799 * @param bool $suppress
2802 final public function setTrxEndCallbackSuppression( $suppress ) {
2803 $this->mTrxEndCallbacksSuppressed
= $suppress;
2807 * Actually run and consume any "on transaction idle/resolution" callbacks.
2809 * This method should not be used outside of Database/LoadBalancer
2811 * @param int $trigger IDatabase::TRIGGER_* constant
2815 public function runOnTransactionIdleCallbacks( $trigger ) {
2816 if ( $this->mTrxEndCallbacksSuppressed
) {
2820 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
2821 /** @var Exception $e */
2822 $e = null; // first exception
2823 do { // callbacks may add callbacks :)
2824 $callbacks = array_merge(
2825 $this->mTrxIdleCallbacks
,
2826 $this->mTrxEndCallbacks
// include "transaction resolution" callbacks
2828 $this->mTrxIdleCallbacks
= []; // consumed (and recursion guard)
2829 $this->mTrxEndCallbacks
= []; // consumed (recursion guard)
2830 foreach ( $callbacks as $callback ) {
2832 list( $phpCallback ) = $callback;
2833 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
2834 call_user_func_array( $phpCallback, [ $trigger ] );
2836 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
2838 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
2840 } catch ( Exception
$ex ) {
2841 call_user_func( $this->errorLogger
, $ex );
2843 // Some callbacks may use startAtomic/endAtomic, so make sure
2844 // their transactions are ended so other callbacks don't fail
2845 if ( $this->trxLevel() ) {
2846 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
2850 } while ( count( $this->mTrxIdleCallbacks
) );
2852 if ( $e instanceof Exception
) {
2853 throw $e; // re-throw any first exception
2858 * Actually run and consume any "on transaction pre-commit" callbacks.
2860 * This method should not be used outside of Database/LoadBalancer
2865 public function runOnTransactionPreCommitCallbacks() {
2866 $e = null; // first exception
2867 do { // callbacks may add callbacks :)
2868 $callbacks = $this->mTrxPreCommitCallbacks
;
2869 $this->mTrxPreCommitCallbacks
= []; // consumed (and recursion guard)
2870 foreach ( $callbacks as $callback ) {
2872 list( $phpCallback ) = $callback;
2873 call_user_func( $phpCallback );
2874 } catch ( Exception
$ex ) {
2875 call_user_func( $this->errorLogger
, $ex );
2879 } while ( count( $this->mTrxPreCommitCallbacks
) );
2881 if ( $e instanceof Exception
) {
2882 throw $e; // re-throw any first exception
2887 * Actually run any "transaction listener" callbacks.
2889 * This method should not be used outside of Database/LoadBalancer
2891 * @param int $trigger IDatabase::TRIGGER_* constant
2895 public function runTransactionListenerCallbacks( $trigger ) {
2896 if ( $this->mTrxEndCallbacksSuppressed
) {
2900 /** @var Exception $e */
2901 $e = null; // first exception
2903 foreach ( $this->mTrxRecurringCallbacks
as $phpCallback ) {
2905 $phpCallback( $trigger, $this );
2906 } catch ( Exception
$ex ) {
2907 call_user_func( $this->errorLogger
, $ex );
2912 if ( $e instanceof Exception
) {
2913 throw $e; // re-throw any first exception
2917 final public function startAtomic( $fname = __METHOD__
) {
2918 if ( !$this->mTrxLevel
) {
2919 $this->begin( $fname, self
::TRANSACTION_INTERNAL
);
2920 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
2921 // in all changes being in one transaction to keep requests transactional.
2922 if ( !$this->getFlag( self
::DBO_TRX
) ) {
2923 $this->mTrxAutomaticAtomic
= true;
2927 $this->mTrxAtomicLevels
[] = $fname;
2930 final public function endAtomic( $fname = __METHOD__
) {
2931 if ( !$this->mTrxLevel
) {
2932 throw new DBUnexpectedError( $this, "No atomic transaction is open (got $fname)." );
2934 if ( !$this->mTrxAtomicLevels ||
2935 array_pop( $this->mTrxAtomicLevels
) !== $fname
2937 throw new DBUnexpectedError( $this, "Invalid atomic section ended (got $fname)." );
2940 if ( !$this->mTrxAtomicLevels
&& $this->mTrxAutomaticAtomic
) {
2941 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
2945 final public function doAtomicSection( $fname, callable
$callback ) {
2946 $this->startAtomic( $fname );
2948 $res = call_user_func_array( $callback, [ $this, $fname ] );
2949 } catch ( Exception
$e ) {
2950 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
2953 $this->endAtomic( $fname );
2958 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
2959 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
2960 if ( $this->mTrxLevel
) {
2961 if ( $this->mTrxAtomicLevels
) {
2962 $levels = implode( ', ', $this->mTrxAtomicLevels
);
2963 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
2964 throw new DBUnexpectedError( $this, $msg );
2965 } elseif ( !$this->mTrxAutomatic
) {
2966 $msg = "$fname: Explicit transaction already active (from {$this->mTrxFname}).";
2967 throw new DBUnexpectedError( $this, $msg );
2969 // @TODO: make this an exception at some point
2970 $msg = "$fname: Implicit transaction already active (from {$this->mTrxFname}).";
2971 $this->queryLogger
->error( $msg );
2972 return; // join the main transaction set
2974 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
2975 // @TODO: make this an exception at some point
2976 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
2977 $this->queryLogger
->error( $msg );
2978 return; // let any writes be in the main transaction
2981 // Avoid fatals if close() was called
2982 $this->assertOpen();
2984 $this->doBegin( $fname );
2985 $this->mTrxTimestamp
= microtime( true );
2986 $this->mTrxFname
= $fname;
2987 $this->mTrxDoneWrites
= false;
2988 $this->mTrxAutomaticAtomic
= false;
2989 $this->mTrxAtomicLevels
= [];
2990 $this->mTrxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
2991 $this->mTrxWriteDuration
= 0.0;
2992 $this->mTrxWriteQueryCount
= 0;
2993 $this->mTrxWriteAffectedRows
= 0;
2994 $this->mTrxWriteAdjDuration
= 0.0;
2995 $this->mTrxWriteAdjQueryCount
= 0;
2996 $this->mTrxWriteCallers
= [];
2997 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
2998 // Get an estimate of the replica DB lag before then, treating estimate staleness
2999 // as lag itself just to be safe
3000 $status = $this->getApproximateLagStatus();
3001 $this->mTrxReplicaLag
= $status['lag'] +
( microtime( true ) - $status['since'] );
3002 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3003 // caller will think its OK to muck around with the transaction just because startAtomic()
3004 // has not yet completed (e.g. setting mTrxAtomicLevels).
3005 $this->mTrxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
3009 * Issues the BEGIN command to the database server.
3011 * @see Database::begin()
3012 * @param string $fname
3014 protected function doBegin( $fname ) {
3015 $this->query( 'BEGIN', $fname );
3016 $this->mTrxLevel
= 1;
3019 final public function commit( $fname = __METHOD__
, $flush = '' ) {
3020 if ( $this->mTrxLevel
&& $this->mTrxAtomicLevels
) {
3021 // There are still atomic sections open. This cannot be ignored
3022 $levels = implode( ', ', $this->mTrxAtomicLevels
);
3023 throw new DBUnexpectedError(
3025 "$fname: Got COMMIT while atomic sections $levels are still open."
3029 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3030 if ( !$this->mTrxLevel
) {
3031 return; // nothing to do
3032 } elseif ( !$this->mTrxAutomatic
) {
3033 throw new DBUnexpectedError(
3035 "$fname: Flushing an explicit transaction, getting out of sync."
3039 if ( !$this->mTrxLevel
) {
3040 $this->queryLogger
->error(
3041 "$fname: No transaction to commit, something got out of sync." );
3042 return; // nothing to do
3043 } elseif ( $this->mTrxAutomatic
) {
3044 // @TODO: make this an exception at some point
3045 $msg = "$fname: Explicit commit of implicit transaction.";
3046 $this->queryLogger
->error( $msg );
3047 return; // wait for the main transaction set commit round
3051 // Avoid fatals if close() was called
3052 $this->assertOpen();
3054 $this->runOnTransactionPreCommitCallbacks();
3055 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
3056 $this->doCommit( $fname );
3057 if ( $this->mTrxDoneWrites
) {
3058 $this->mLastWriteTime
= microtime( true );
3059 $this->trxProfiler
->transactionWritingOut(
3064 $this->mTrxWriteAffectedRows
3068 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
3069 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
3073 * Issues the COMMIT command to the database server.
3075 * @see Database::commit()
3076 * @param string $fname
3078 protected function doCommit( $fname ) {
3079 if ( $this->mTrxLevel
) {
3080 $this->query( 'COMMIT', $fname );
3081 $this->mTrxLevel
= 0;
3085 final public function rollback( $fname = __METHOD__
, $flush = '' ) {
3086 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3087 if ( !$this->mTrxLevel
) {
3088 return; // nothing to do
3091 if ( !$this->mTrxLevel
) {
3092 $this->queryLogger
->error(
3093 "$fname: No transaction to rollback, something got out of sync." );
3094 return; // nothing to do
3095 } elseif ( $this->getFlag( self
::DBO_TRX
) ) {
3096 throw new DBUnexpectedError(
3098 "$fname: Expected mass rollback of all peer databases (DBO_TRX set)."
3103 // Avoid fatals if close() was called
3104 $this->assertOpen();
3106 $this->doRollback( $fname );
3107 $this->mTrxAtomicLevels
= [];
3108 if ( $this->mTrxDoneWrites
) {
3109 $this->trxProfiler
->transactionWritingOut(
3116 $this->mTrxIdleCallbacks
= []; // clear
3117 $this->mTrxPreCommitCallbacks
= []; // clear
3119 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
3120 } catch ( Exception
$e ) {
3121 // already logged; finish and let LoadBalancer move on during mass-rollback
3124 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
3125 } catch ( Exception
$e ) {
3126 // already logged; let LoadBalancer move on during mass-rollback
3131 * Issues the ROLLBACK command to the database server.
3133 * @see Database::rollback()
3134 * @param string $fname
3136 protected function doRollback( $fname ) {
3137 if ( $this->mTrxLevel
) {
3138 # Disconnects cause rollback anyway, so ignore those errors
3139 $ignoreErrors = true;
3140 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
3141 $this->mTrxLevel
= 0;
3145 public function flushSnapshot( $fname = __METHOD__
) {
3146 if ( $this->writesOrCallbacksPending() ||
$this->explicitTrxActive() ) {
3147 // This only flushes transactions to clear snapshots, not to write data
3148 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
3149 throw new DBUnexpectedError(
3151 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
3155 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3158 public function explicitTrxActive() {
3159 return $this->mTrxLevel
&& ( $this->mTrxAtomicLevels ||
!$this->mTrxAutomatic
);
3162 public function duplicateTableStructure(
3163 $oldName, $newName, $temporary = false, $fname = __METHOD__
3165 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3168 public function listTables( $prefix = null, $fname = __METHOD__
) {
3169 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3172 public function listViews( $prefix = null, $fname = __METHOD__
) {
3173 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3176 public function timestamp( $ts = 0 ) {
3177 $t = new ConvertibleTimestamp( $ts );
3178 // Let errors bubble up to avoid putting garbage in the DB
3179 return $t->getTimestamp( TS_MW
);
3182 public function timestampOrNull( $ts = null ) {
3183 if ( is_null( $ts ) ) {
3186 return $this->timestamp( $ts );
3191 * Take the result from a query, and wrap it in a ResultWrapper if
3192 * necessary. Boolean values are passed through as is, to indicate success
3193 * of write queries or failure.
3195 * Once upon a time, Database::query() returned a bare MySQL result
3196 * resource, and it was necessary to call this function to convert it to
3197 * a wrapper. Nowadays, raw database objects are never exposed to external
3198 * callers, so this is unnecessary in external code.
3200 * @param bool|ResultWrapper|resource|object $result
3201 * @return bool|ResultWrapper
3203 protected function resultObject( $result ) {
3206 } elseif ( $result instanceof ResultWrapper
) {
3208 } elseif ( $result === true ) {
3209 // Successful write query
3212 return new ResultWrapper( $this, $result );
3216 public function ping( &$rtt = null ) {
3217 // Avoid hitting the server if it was hit recently
3218 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::PING_TTL
) {
3219 if ( !func_num_args() ||
$this->mRTTEstimate
> 0 ) {
3220 $rtt = $this->mRTTEstimate
;
3221 return true; // don't care about $rtt
3225 // This will reconnect if possible or return false if not
3226 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
3227 $ok = ( $this->query( self
::PING_QUERY
, __METHOD__
, true ) !== false );
3228 $this->restoreFlags( self
::RESTORE_PRIOR
);
3231 $rtt = $this->mRTTEstimate
;
3238 * Close existing database connection and open a new connection
3240 * @return bool True if new connection is opened successfully, false if error
3242 protected function reconnect() {
3243 $this->closeConnection();
3244 $this->mOpened
= false;
3245 $this->mConn
= false;
3247 $this->open( $this->mServer
, $this->mUser
, $this->mPassword
, $this->mDBname
);
3248 $this->lastPing
= microtime( true );
3250 } catch ( DBConnectionError
$e ) {
3257 public function getSessionLagStatus() {
3258 return $this->getTransactionLagStatus() ?
: $this->getApproximateLagStatus();
3262 * Get the replica DB lag when the current transaction started
3264 * This is useful when transactions might use snapshot isolation
3265 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
3266 * is this lag plus transaction duration. If they don't, it is still
3267 * safe to be pessimistic. This returns null if there is no transaction.
3269 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
3272 protected function getTransactionLagStatus() {
3273 return $this->mTrxLevel
3274 ?
[ 'lag' => $this->mTrxReplicaLag
, 'since' => $this->trxTimestamp() ]
3279 * Get a replica DB lag estimate for this server
3281 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
3284 protected function getApproximateLagStatus() {
3286 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
3287 'since' => microtime( true )
3292 * Merge the result of getSessionLagStatus() for several DBs
3293 * using the most pessimistic values to estimate the lag of
3294 * any data derived from them in combination
3296 * This is information is useful for caching modules
3298 * @see WANObjectCache::set()
3299 * @see WANObjectCache::getWithSetCallback()
3301 * @param IDatabase $db1
3302 * @param IDatabase $db2 [optional]
3303 * @return array Map of values:
3304 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
3305 * - since: oldest UNIX timestamp of any of the DB lag estimates
3306 * - pending: whether any of the DBs have uncommitted changes
3310 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
3311 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
3312 foreach ( func_get_args() as $db ) {
3313 /** @var IDatabase $db */
3314 $status = $db->getSessionLagStatus();
3315 if ( $status['lag'] === false ) {
3316 $res['lag'] = false;
3317 } elseif ( $res['lag'] !== false ) {
3318 $res['lag'] = max( $res['lag'], $status['lag'] );
3320 $res['since'] = min( $res['since'], $status['since'] );
3321 $res['pending'] = $res['pending'] ?
: $db->writesPending();
3327 public function getLag() {
3331 public function maxListLen() {
3335 public function encodeBlob( $b ) {
3339 public function decodeBlob( $b ) {
3340 if ( $b instanceof Blob
) {
3346 public function setSessionOptions( array $options ) {
3349 public function sourceFile(
3351 callable
$lineCallback = null,
3352 callable
$resultCallback = null,
3354 callable
$inputCallback = null
3356 MediaWiki\
suppressWarnings();
3357 $fp = fopen( $filename, 'r' );
3358 MediaWiki\restoreWarnings
();
3360 if ( false === $fp ) {
3361 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
3365 $fname = __METHOD__
. "( $filename )";
3369 $error = $this->sourceStream(
3370 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
3371 } catch ( Exception
$e ) {
3381 public function setSchemaVars( $vars ) {
3382 $this->mSchemaVars
= $vars;
3385 public function sourceStream(
3387 callable
$lineCallback = null,
3388 callable
$resultCallback = null,
3389 $fname = __METHOD__
,
3390 callable
$inputCallback = null
3392 $delimiterReset = new ScopedCallback(
3393 function ( $delimiter ) {
3394 $this->delimiter
= $delimiter;
3396 [ $this->delimiter
]
3400 while ( !feof( $fp ) ) {
3401 if ( $lineCallback ) {
3402 call_user_func( $lineCallback );
3405 $line = trim( fgets( $fp ) );
3407 if ( $line == '' ) {
3411 if ( '-' == $line[0] && '-' == $line[1] ) {
3419 $done = $this->streamStatementEnd( $cmd, $line );
3423 if ( $done ||
feof( $fp ) ) {
3424 $cmd = $this->replaceVars( $cmd );
3426 if ( $inputCallback ) {
3427 $callbackResult = call_user_func( $inputCallback, $cmd );
3429 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
3430 $cmd = $callbackResult;
3435 $res = $this->query( $cmd, $fname );
3437 if ( $resultCallback ) {
3438 call_user_func( $resultCallback, $res, $this );
3441 if ( false === $res ) {
3442 $err = $this->lastError();
3444 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
3451 ScopedCallback
::consume( $delimiterReset );
3456 * Called by sourceStream() to check if we've reached a statement end
3458 * @param string &$sql SQL assembled so far
3459 * @param string &$newLine New line about to be added to $sql
3460 * @return bool Whether $newLine contains end of the statement
3462 public function streamStatementEnd( &$sql, &$newLine ) {
3463 if ( $this->delimiter
) {
3465 $newLine = preg_replace(
3466 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
3467 if ( $newLine != $prev ) {
3476 * Database independent variable replacement. Replaces a set of variables
3477 * in an SQL statement with their contents as given by $this->getSchemaVars().
3479 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
3481 * - '{$var}' should be used for text and is passed through the database's
3483 * - `{$var}` should be used for identifiers (e.g. table and database names).
3484 * It is passed through the database's addIdentifierQuotes method which
3485 * can be overridden if the database uses something other than backticks.
3486 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
3487 * database's tableName method.
3488 * - / *i* / passes the name that follows through the database's indexName method.
3489 * - In all other cases, / *$var* / is left unencoded. Except for table options,
3490 * its use should be avoided. In 1.24 and older, string encoding was applied.
3492 * @param string $ins SQL statement to replace variables in
3493 * @return string The new SQL statement with variables replaced
3495 protected function replaceVars( $ins ) {
3496 $vars = $this->getSchemaVars();
3497 return preg_replace_callback(
3499 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
3500 \'\{\$ (\w+) }\' | # 3. addQuotes
3501 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
3502 /\*\$ (\w+) \*/ # 5. leave unencoded
3504 function ( $m ) use ( $vars ) {
3505 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
3506 // check for both nonexistent keys *and* the empty string.
3507 if ( isset( $m[1] ) && $m[1] !== '' ) {
3508 if ( $m[1] === 'i' ) {
3509 return $this->indexName( $m[2] );
3511 return $this->tableName( $m[2] );
3513 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
3514 return $this->addQuotes( $vars[$m[3]] );
3515 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
3516 return $this->addIdentifierQuotes( $vars[$m[4]] );
3517 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
3518 return $vars[$m[5]];
3528 * Get schema variables. If none have been set via setSchemaVars(), then
3529 * use some defaults from the current object.
3533 protected function getSchemaVars() {
3534 if ( $this->mSchemaVars
) {
3535 return $this->mSchemaVars
;
3537 return $this->getDefaultSchemaVars();
3542 * Get schema variables to use if none have been set via setSchemaVars().
3544 * Override this in derived classes to provide variables for tables.sql
3545 * and SQL patch files.
3549 protected function getDefaultSchemaVars() {
3553 public function lockIsFree( $lockName, $method ) {
3557 public function lock( $lockName, $method, $timeout = 5 ) {
3558 $this->mNamedLocksHeld
[$lockName] = 1;
3563 public function unlock( $lockName, $method ) {
3564 unset( $this->mNamedLocksHeld
[$lockName] );
3569 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
3570 if ( $this->writesOrCallbacksPending() ) {
3571 // This only flushes transactions to clear snapshots, not to write data
3572 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
3573 throw new DBUnexpectedError(
3575 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
3579 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
3583 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
3584 if ( $this->trxLevel() ) {
3585 // There is a good chance an exception was thrown, causing any early return
3586 // from the caller. Let any error handler get a chance to issue rollback().
3587 // If there isn't one, let the error bubble up and trigger server-side rollback.
3588 $this->onTransactionResolution(
3589 function () use ( $lockKey, $fname ) {
3590 $this->unlock( $lockKey, $fname );
3595 $this->unlock( $lockKey, $fname );
3599 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3604 public function namedLocksEnqueue() {
3608 public function tableLocksHaveTransactionScope() {
3612 final public function lockTables( array $read, array $write, $method ) {
3613 if ( $this->writesOrCallbacksPending() ) {
3614 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
3617 if ( $this->tableLocksHaveTransactionScope() ) {
3618 $this->startAtomic( $method );
3621 return $this->doLockTables( $read, $write, $method );
3625 * Helper function for lockTables() that handles the actual table locking
3627 * @param array $read Array of tables to lock for read access
3628 * @param array $write Array of tables to lock for write access
3629 * @param string $method Name of caller
3632 protected function doLockTables( array $read, array $write, $method ) {
3636 final public function unlockTables( $method ) {
3637 if ( $this->tableLocksHaveTransactionScope() ) {
3638 $this->endAtomic( $method );
3640 return true; // locks released on COMMIT/ROLLBACK
3643 return $this->doUnlockTables( $method );
3647 * Helper function for unlockTables() that handles the actual table unlocking
3649 * @param string $method Name of caller
3652 protected function doUnlockTables( $method ) {
3658 * @param string $tableName
3659 * @param string $fName
3660 * @return bool|ResultWrapper
3663 public function dropTable( $tableName, $fName = __METHOD__
) {
3664 if ( !$this->tableExists( $tableName, $fName ) ) {
3667 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
3669 return $this->query( $sql, $fName );
3672 public function getInfinity() {
3676 public function encodeExpiry( $expiry ) {
3677 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
3678 ?
$this->getInfinity()
3679 : $this->timestamp( $expiry );
3682 public function decodeExpiry( $expiry, $format = TS_MW
) {
3683 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
3687 return ConvertibleTimestamp
::convert( $format, $expiry );
3690 public function setBigSelects( $value = true ) {
3694 public function isReadOnly() {
3695 return ( $this->getReadOnlyReason() !== false );
3699 * @return string|bool Reason this DB is read-only or false if it is not
3701 protected function getReadOnlyReason() {
3702 $reason = $this->getLBInfo( 'readOnlyReason' );
3704 return is_string( $reason ) ?
$reason : false;
3707 public function setTableAliases( array $aliases ) {
3708 $this->tableAliases
= $aliases;
3712 * @return bool Whether a DB user is required to access the DB
3715 protected function requiresDatabaseUser() {
3720 * Get the underlying binding handle, mConn
3722 * Makes sure that mConn is set (disconnects and ping() failure can unset it).
3723 * This catches broken callers than catch and ignore disconnection exceptions.
3724 * Unlike checking isOpen(), this is safe to call inside of open().
3726 * @return resource|object
3727 * @throws DBUnexpectedError
3730 protected function getBindingHandle() {
3731 if ( !$this->mConn
) {
3732 throw new DBUnexpectedError(
3734 'DB connection was already closed or the connection dropped.'
3738 return $this->mConn
;
3745 public function __toString() {
3746 return (string)$this->mConn
;
3750 * Make sure that copies do not share the same client binding handle
3751 * @throws DBConnectionError
3753 public function __clone() {
3754 $this->connLogger
->warning(
3755 "Cloning " . static::class . " is not recomended; forking connection:\n" .
3756 ( new RuntimeException() )->getTraceAsString()
3759 if ( $this->isOpen() ) {
3760 // Open a new connection resource without messing with the old one
3761 $this->mOpened
= false;
3762 $this->mConn
= false;
3763 $this->mTrxEndCallbacks
= []; // don't copy
3764 $this->handleSessionLoss(); // no trx or locks anymore
3765 $this->open( $this->mServer
, $this->mUser
, $this->mPassword
, $this->mDBname
);
3766 $this->lastPing
= microtime( true );
3771 * Called by serialize. Throw an exception when DB connection is serialized.
3772 * This causes problems on some database engines because the connection is
3773 * not restored on unserialize.
3775 public function __sleep() {
3776 throw new RuntimeException( 'Database serialization may cause problems, since ' .
3777 'the connection is not restored on wakeup.' );
3781 * Run a few simple sanity checks and close dangling connections
3783 public function __destruct() {
3784 if ( $this->mTrxLevel
&& $this->mTrxDoneWrites
) {
3785 trigger_error( "Uncommitted DB writes (transaction from {$this->mTrxFname})." );
3788 $danglingWriters = $this->pendingWriteAndCallbackCallers();
3789 if ( $danglingWriters ) {
3790 $fnames = implode( ', ', $danglingWriters );
3791 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
3794 if ( $this->mConn
) {
3795 // Avoid connection leaks for sanity. Normally, resources close at script completion.
3796 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
3797 \MediaWiki\
suppressWarnings();
3798 $this->closeConnection();
3799 \MediaWiki\restoreWarnings
();
3800 $this->mConn
= false;
3801 $this->mOpened
= false;
3806 class_alias( Database
::class, 'DatabaseBase' ); // b/c for old name
3807 class_alias( Database
::class, 'Database' ); // b/c global alias