3 * This is the MySQL database abstraction layer.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
23 namespace Wikimedia\Rdbms
;
28 use InvalidArgumentException
;
33 * Database abstraction object for MySQL.
34 * Defines methods independent on used MySQL extension.
40 abstract class DatabaseMysqlBase
extends Database
{
41 /** @var MysqlMasterPos */
42 protected $lastKnownReplicaPos;
43 /** @var string Method to detect replica DB lag */
44 protected $lagDetectionMethod;
45 /** @var array Method to detect replica DB lag */
46 protected $lagDetectionOptions = [];
47 /** @var bool bool Whether to use GTID methods */
48 protected $useGTIDs = false;
49 /** @var string|null */
50 protected $sslKeyPath;
51 /** @var string|null */
52 protected $sslCertPath;
53 /** @var string|null */
55 /** @var string|null */
57 /** @var string[]|null */
58 protected $sslCiphers;
59 /** @var string sql_mode value to send on connection */
61 /** @var bool Use experimental UTF-8 transmission encoding */
64 protected $defaultBigSelects = null;
66 /** @var string|null */
67 private $serverVersion = null;
69 private $insertSelectIsSafe = null;
70 /** @var stdClass|null */
71 private $replicationInfoRow = null;
73 // Cache getServerId() for 24 hours
74 const SERVER_ID_CACHE_TTL
= 86400;
76 /** @var float Warn if lag estimates are made for transactions older than this many seconds */
77 const LAG_STALE_WARN_THRESHOLD
= 0.100;
80 * Additional $params include:
81 * - lagDetectionMethod : set to one of (Seconds_Behind_Master,pt-heartbeat).
82 * pt-heartbeat assumes the table is at heartbeat.heartbeat
83 * and uses UTC timestamps in the heartbeat.ts column.
84 * (https://www.percona.com/doc/percona-toolkit/2.2/pt-heartbeat.html)
85 * - lagDetectionOptions : if using pt-heartbeat, this can be set to an array map to change
86 * the default behavior. Normally, the heartbeat row with the server
87 * ID of this server's master will be used. Set the "conds" field to
88 * override the query conditions, e.g. ['shard' => 's1'].
89 * - useGTIDs : use GTID methods like MASTER_GTID_WAIT() when possible.
90 * - insertSelectIsSafe : force that native INSERT SELECT is or is not safe [default: null]
91 * - sslKeyPath : path to key file [default: null]
92 * - sslCertPath : path to certificate file [default: null]
93 * - sslCAFile: path to a single certificate authority PEM file [default: null]
94 * - sslCAPath : parth to certificate authority PEM directory [default: null]
95 * - sslCiphers : array list of allowable ciphers [default: null]
96 * @param array $params
98 function __construct( array $params ) {
99 $this->lagDetectionMethod
= isset( $params['lagDetectionMethod'] )
100 ?
$params['lagDetectionMethod']
101 : 'Seconds_Behind_Master';
102 $this->lagDetectionOptions
= isset( $params['lagDetectionOptions'] )
103 ?
$params['lagDetectionOptions']
105 $this->useGTIDs
= !empty( $params['useGTIDs' ] );
106 foreach ( [ 'KeyPath', 'CertPath', 'CAFile', 'CAPath', 'Ciphers' ] as $name ) {
108 if ( isset( $params[$var] ) ) {
109 $this->$var = $params[$var];
112 $this->sqlMode
= isset( $params['sqlMode'] ) ?
$params['sqlMode'] : '';
113 $this->utf8Mode
= !empty( $params['utf8Mode'] );
114 $this->insertSelectIsSafe
= isset( $params['insertSelectIsSafe'] )
115 ?
(bool)$params['insertSelectIsSafe'] : null;
117 parent
::__construct( $params );
123 public function getType() {
128 * @param string $server
129 * @param string $user
130 * @param string $password
131 * @param string $dbName
132 * @throws Exception|DBConnectionError
135 public function open( $server, $user, $password, $dbName ) {
136 # Close/unset connection handle
139 $this->server
= $server;
141 $this->password
= $password;
142 $this->dbName
= $dbName;
144 $this->installErrorHandler();
146 $this->conn
= $this->mysqlConnect( $this->server
);
147 } catch ( Exception
$ex ) {
148 $this->restoreErrorHandler();
151 $error = $this->restoreErrorHandler();
153 # Always log connection errors
154 if ( !$this->conn
) {
156 $error = $this->lastError();
158 $this->connLogger
->error(
159 "Error connecting to {db_server}: {error}",
160 $this->getLogContext( [
161 'method' => __METHOD__
,
165 $this->connLogger
->debug( "DB connection error\n" .
166 "Server: $server, User: $user, Password: " .
167 substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
169 $this->reportConnectionError( $error );
172 if ( strlen( $dbName ) ) {
173 Wikimedia\
suppressWarnings();
174 $success = $this->selectDB( $dbName );
175 Wikimedia\restoreWarnings
();
177 $this->queryLogger
->error(
178 "Error selecting database {db_name} on server {db_server}",
179 $this->getLogContext( [
180 'method' => __METHOD__
,
183 $this->queryLogger
->debug(
184 "Error selecting database $dbName on server {$this->server}" );
186 $this->reportConnectionError( "Error selecting database $dbName" );
190 // Tell the server what we're communicating with
191 if ( !$this->connectInitCharset() ) {
192 $this->reportConnectionError( "Error setting character set" );
195 // Abstract over any insane MySQL defaults
196 $set = [ 'group_concat_max_len = 262144' ];
197 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
198 if ( is_string( $this->sqlMode
) ) {
199 $set[] = 'sql_mode = ' . $this->addQuotes( $this->sqlMode
);
201 // Set any custom settings defined by site config
202 // (e.g. https://dev.mysql.com/doc/refman/4.1/en/innodb-parameters.html)
203 foreach ( $this->sessionVars
as $var => $val ) {
204 // Escape strings but not numbers to avoid MySQL complaining
205 if ( !is_int( $val ) && !is_float( $val ) ) {
206 $val = $this->addQuotes( $val );
208 $set[] = $this->addIdentifierQuotes( $var ) . ' = ' . $val;
212 // Use doQuery() to avoid opening implicit transactions (DBO_TRX)
213 $success = $this->doQuery( 'SET ' . implode( ', ', $set ) );
215 $this->queryLogger
->error(
216 'Error setting MySQL variables on server {db_server} (check $wgSQLMode)',
217 $this->getLogContext( [
218 'method' => __METHOD__
,
221 $this->reportConnectionError(
222 'Error setting MySQL variables on server {db_server} (check $wgSQLMode)' );
226 $this->opened
= true;
232 * Set the character set information right after connection
235 protected function connectInitCharset() {
236 if ( $this->utf8Mode
) {
237 // Tell the server we're communicating with it in UTF-8.
238 // This may engage various charset conversions.
239 return $this->mysqlSetCharset( 'utf8' );
241 return $this->mysqlSetCharset( 'binary' );
246 * Open a connection to a MySQL server
248 * @param string $realServer
249 * @return mixed Raw connection
250 * @throws DBConnectionError
252 abstract protected function mysqlConnect( $realServer );
255 * Set the character set of the MySQL link
257 * @param string $charset
260 abstract protected function mysqlSetCharset( $charset );
263 * @param ResultWrapper|resource $res
264 * @throws DBUnexpectedError
266 public function freeResult( $res ) {
267 if ( $res instanceof ResultWrapper
) {
270 Wikimedia\
suppressWarnings();
271 $ok = $this->mysqlFreeResult( $res );
272 Wikimedia\restoreWarnings
();
274 throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
281 * @param resource $res Raw result
284 abstract protected function mysqlFreeResult( $res );
287 * @param ResultWrapper|resource $res
288 * @return stdClass|bool
289 * @throws DBUnexpectedError
291 public function fetchObject( $res ) {
292 if ( $res instanceof ResultWrapper
) {
295 Wikimedia\
suppressWarnings();
296 $row = $this->mysqlFetchObject( $res );
297 Wikimedia\restoreWarnings
();
299 $errno = $this->lastErrno();
300 // Unfortunately, mysql_fetch_object does not reset the last errno.
301 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
302 // these are the only errors mysql_fetch_object can cause.
303 // See https://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
304 if ( $errno == 2000 ||
$errno == 2013 ) {
305 throw new DBUnexpectedError(
307 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
315 * Fetch a result row as an object
317 * @param resource $res Raw result
320 abstract protected function mysqlFetchObject( $res );
323 * @param ResultWrapper|resource $res
325 * @throws DBUnexpectedError
327 public function fetchRow( $res ) {
328 if ( $res instanceof ResultWrapper
) {
331 Wikimedia\
suppressWarnings();
332 $row = $this->mysqlFetchArray( $res );
333 Wikimedia\restoreWarnings
();
335 $errno = $this->lastErrno();
336 // Unfortunately, mysql_fetch_array does not reset the last errno.
337 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
338 // these are the only errors mysql_fetch_array can cause.
339 // See https://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
340 if ( $errno == 2000 ||
$errno == 2013 ) {
341 throw new DBUnexpectedError(
343 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
351 * Fetch a result row as an associative and numeric array
353 * @param resource $res Raw result
356 abstract protected function mysqlFetchArray( $res );
359 * @throws DBUnexpectedError
360 * @param ResultWrapper|resource $res
363 function numRows( $res ) {
364 if ( $res instanceof ResultWrapper
) {
367 Wikimedia\
suppressWarnings();
368 $n = $this->mysqlNumRows( $res );
369 Wikimedia\restoreWarnings
();
371 // Unfortunately, mysql_num_rows does not reset the last errno.
372 // We are not checking for any errors here, since
373 // these are no errors mysql_num_rows can cause.
374 // See https://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
375 // See https://phabricator.wikimedia.org/T44430
380 * Get number of rows in result
382 * @param resource $res Raw result
385 abstract protected function mysqlNumRows( $res );
388 * @param ResultWrapper|resource $res
391 public function numFields( $res ) {
392 if ( $res instanceof ResultWrapper
) {
396 return $this->mysqlNumFields( $res );
400 * Get number of fields in result
402 * @param resource $res Raw result
405 abstract protected function mysqlNumFields( $res );
408 * @param ResultWrapper|resource $res
412 public function fieldName( $res, $n ) {
413 if ( $res instanceof ResultWrapper
) {
417 return $this->mysqlFieldName( $res, $n );
421 * Get the name of the specified field in a result
423 * @param ResultWrapper|resource $res
427 abstract protected function mysqlFieldName( $res, $n );
430 * mysql_field_type() wrapper
431 * @param ResultWrapper|resource $res
435 public function fieldType( $res, $n ) {
436 if ( $res instanceof ResultWrapper
) {
440 return $this->mysqlFieldType( $res, $n );
444 * Get the type of the specified field in a result
446 * @param ResultWrapper|resource $res
450 abstract protected function mysqlFieldType( $res, $n );
453 * @param ResultWrapper|resource $res
457 public function dataSeek( $res, $row ) {
458 if ( $res instanceof ResultWrapper
) {
462 return $this->mysqlDataSeek( $res, $row );
466 * Move internal result pointer
468 * @param ResultWrapper|resource $res
472 abstract protected function mysqlDataSeek( $res, $row );
477 public function lastError() {
479 # Even if it's non-zero, it can still be invalid
480 Wikimedia\
suppressWarnings();
481 $error = $this->mysqlError( $this->conn
);
483 $error = $this->mysqlError();
485 Wikimedia\restoreWarnings
();
487 $error = $this->mysqlError();
490 $error .= ' (' . $this->server
. ')';
497 * Returns the text of the error message from previous MySQL operation
499 * @param resource $conn Raw connection
502 abstract protected function mysqlError( $conn = null );
504 protected function wasQueryTimeout( $error, $errno ) {
505 return $errno == 2062;
509 * @param string $table
510 * @param array $uniqueIndexes
512 * @param string $fname
513 * @return ResultWrapper
515 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
516 return $this->nativeReplace( $table, $rows, $fname );
519 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
520 $row = $this->getReplicationSafetyInfo();
521 // For row-based-replication, the resulting changes will be relayed, not the query
522 if ( $row->binlog_format
=== 'ROW' ) {
525 // LIMIT requires ORDER BY on a unique key or it is non-deterministic
526 if ( isset( $selectOptions['LIMIT'] ) ) {
529 // In MySQL, an INSERT SELECT is only replication safe with row-based
530 // replication or if innodb_autoinc_lock_mode is 0. When those
531 // conditions aren't met, use non-native mode.
532 // While we could try to determine if the insert is safe anyway by
533 // checking if the target table has an auto-increment column that
534 // isn't set in $varMap, that seems unlikely to be worth the extra
537 in_array( 'NO_AUTO_COLUMNS', $insertOptions ) ||
538 (int)$row->innodb_autoinc_lock_mode
=== 0
543 * @return stdClass Process cached row
545 protected function getReplicationSafetyInfo() {
546 if ( $this->replicationInfoRow
=== null ) {
547 $this->replicationInfoRow
= $this->selectRow(
550 'innodb_autoinc_lock_mode' => '@@innodb_autoinc_lock_mode',
551 'binlog_format' => '@@binlog_format',
558 return $this->replicationInfoRow
;
562 * Estimate rows in dataset
563 * Returns estimated count, based on EXPLAIN output
564 * Takes same arguments as Database::select()
566 * @param string|array $table
567 * @param string|array $var
568 * @param string|array $conds
569 * @param string $fname
570 * @param string|array $options
571 * @param array $join_conds
574 public function estimateRowCount( $table, $var = '*', $conds = '',
575 $fname = __METHOD__
, $options = [], $join_conds = []
577 $conds = $this->normalizeConditions( $conds, $fname );
578 $column = $this->extractSingleFieldFromList( $var );
579 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
580 $conds[] = "$column IS NOT NULL";
583 $options['EXPLAIN'] = true;
584 $res = $this->select( $table, $var, $conds, $fname, $options, $join_conds );
585 if ( $res === false ) {
588 if ( !$this->numRows( $res ) ) {
593 foreach ( $res as $plan ) {
594 $rows *= $plan->rows
> 0 ?
$plan->rows
: 1; // avoid resetting to zero
600 public function tableExists( $table, $fname = __METHOD__
) {
601 // Split database and table into proper variables as Database::tableName() returns
602 // shared tables prefixed with their database, which do not work in SHOW TABLES statements
603 list( $database, , $prefix, $table ) = $this->qualifiedTableComponents( $table );
604 $tableName = "{$prefix}{$table}";
606 if ( isset( $this->sessionTempTables
[$tableName] ) ) {
607 return true; // already known to exist and won't show in SHOW TABLES anyway
610 // We can't use buildLike() here, because it specifies an escape character
611 // other than the backslash, which is the only one supported by SHOW TABLES
612 $encLike = $this->escapeLikeInternal( $tableName, '\\' );
614 // If the database has been specified (such as for shared tables), use "FROM"
615 if ( $database !== '' ) {
616 $encDatabase = $this->addIdentifierQuotes( $database );
617 $query = "SHOW TABLES FROM $encDatabase LIKE '$encLike'";
619 $query = "SHOW TABLES LIKE '$encLike'";
622 return $this->query( $query, $fname )->numRows() > 0;
626 * @param string $table
627 * @param string $field
628 * @return bool|MySQLField
630 public function fieldInfo( $table, $field ) {
631 $table = $this->tableName( $table );
632 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__
, true );
636 $n = $this->mysqlNumFields( $res->result
);
637 for ( $i = 0; $i < $n; $i++
) {
638 $meta = $this->mysqlFetchField( $res->result
, $i );
639 if ( $field == $meta->name
) {
640 return new MySQLField( $meta );
648 * Get column information from a result
650 * @param resource $res Raw result
654 abstract protected function mysqlFetchField( $res, $n );
657 * Get information about an index into an object
658 * Returns false if the index does not exist
660 * @param string $table
661 * @param string $index
662 * @param string $fname
663 * @return bool|array|null False or null on failure
665 public function indexInfo( $table, $index, $fname = __METHOD__
) {
666 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
667 # SHOW INDEX should work for 3.x and up:
668 # https://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
669 $table = $this->tableName( $table );
670 $index = $this->indexName( $index );
672 $sql = 'SHOW INDEX FROM ' . $table;
673 $res = $this->query( $sql, $fname );
681 foreach ( $res as $row ) {
682 if ( $row->Key_name
== $index ) {
687 return $result ?
: false;
694 public function strencode( $s ) {
695 return $this->mysqlRealEscapeString( $s );
702 abstract protected function mysqlRealEscapeString( $s );
704 public function addQuotes( $s ) {
705 if ( is_bool( $s ) ) {
706 // Parent would transform to int, which does not play nice with MySQL type juggling.
707 // When searching for an int in a string column, the strings are cast to int, which
708 // means false would match any string not starting with a number.
709 $s = (string)(int)$s;
711 return parent
::addQuotes( $s );
715 * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
720 public function addIdentifierQuotes( $s ) {
721 // Characters in the range \u0001-\uFFFF are valid in a quoted identifier
722 // Remove NUL bytes and escape backticks by doubling
723 return '`' . str_replace( [ "\0", '`' ], [ '', '``' ], $s ) . '`';
727 * @param string $name
730 public function isQuotedIdentifier( $name ) {
731 return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
734 public function getLag() {
735 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
736 return $this->getLagFromPtHeartbeat();
738 return $this->getLagFromSlaveStatus();
745 protected function getLagDetectionMethod() {
746 return $this->lagDetectionMethod
;
752 protected function getLagFromSlaveStatus() {
753 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__
);
754 $row = $res ?
$res->fetchObject() : false;
755 // If the server is not replicating, there will be no row
756 if ( $row && strval( $row->Seconds_Behind_Master
) !== '' ) {
757 return intval( $row->Seconds_Behind_Master
);
766 protected function getLagFromPtHeartbeat() {
767 $options = $this->lagDetectionOptions
;
769 $staleness = $this->trxLevel
770 ?
microtime( true ) - $this->trxTimestamp()
772 if ( $staleness > self
::LAG_STALE_WARN_THRESHOLD
) {
773 // Avoid returning higher and higher lag value due to snapshot age
774 // given that the isolation level will typically be REPEATABLE-READ
775 $this->queryLogger
->warning(
776 "Using cached lag value for {db_server} due to active transaction",
777 $this->getLogContext( [ 'method' => __METHOD__
] )
780 return $this->getTransactionLagStatus()['lag'];
783 if ( isset( $options['conds'] ) ) {
784 // Best method for multi-DC setups: use logical channel names
785 $data = $this->getHeartbeatData( $options['conds'] );
787 // Standard method: use master server ID (works with stock pt-heartbeat)
788 $masterInfo = $this->getMasterServerInfo();
789 if ( !$masterInfo ) {
790 $this->queryLogger
->error(
791 "Unable to query master of {db_server} for server ID",
792 $this->getLogContext( [
793 'method' => __METHOD__
797 return false; // could not get master server ID
800 $conds = [ 'server_id' => intval( $masterInfo['serverId'] ) ];
801 $data = $this->getHeartbeatData( $conds );
804 list( $time, $nowUnix ) = $data;
805 if ( $time !== null ) {
806 // @time is in ISO format like "2015-09-25T16:48:10.000510"
807 $dateTime = new DateTime( $time, new DateTimeZone( 'UTC' ) );
808 $timeUnix = (int)$dateTime->format( 'U' ) +
$dateTime->format( 'u' ) / 1e6
;
810 return max( $nowUnix - $timeUnix, 0.0 );
813 $this->queryLogger
->error(
814 "Unable to find pt-heartbeat row for {db_server}",
815 $this->getLogContext( [
816 'method' => __METHOD__
823 protected function getMasterServerInfo() {
824 $cache = $this->srvCache
;
825 $key = $cache->makeGlobalKey(
828 // Using one key for all cluster replica DBs is preferable
829 $this->getLBInfo( 'clusterMasterHost' ) ?
: $this->getServer()
832 return $cache->getWithSetCallback(
834 $cache::TTL_INDEFINITE
,
835 function () use ( $cache, $key ) {
836 // Get and leave a lock key in place for a short period
837 if ( !$cache->lock( $key, 0, 10 ) ) {
838 return false; // avoid master connection spike slams
841 $conn = $this->getLazyMasterHandle();
843 return false; // something is misconfigured
846 // Connect to and query the master; catch errors to avoid outages
848 $res = $conn->query( 'SELECT @@server_id AS id', __METHOD__
);
849 $row = $res ?
$res->fetchObject() : false;
850 $id = $row ?
(int)$row->id
: 0;
851 } catch ( DBError
$e ) {
855 // Cache the ID if it was retrieved
856 return $id ?
[ 'serverId' => $id, 'asOf' => time() ] : false;
862 * @param array $conds WHERE clause conditions to find a row
863 * @return array (heartbeat `ts` column value or null, UNIX timestamp) for the newest beat
864 * @see https://www.percona.com/doc/percona-toolkit/2.1/pt-heartbeat.html
866 protected function getHeartbeatData( array $conds ) {
867 // Query time and trip time are not counted
868 $nowUnix = microtime( true );
869 // Do not bother starting implicit transactions here
870 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
872 $whereSQL = $this->makeList( $conds, self
::LIST_AND
);
873 // Use ORDER BY for channel based queries since that field might not be UNIQUE.
874 // Note: this would use "TIMESTAMPDIFF(MICROSECOND,ts,UTC_TIMESTAMP(6))" but the
875 // percision field is not supported in MySQL <= 5.5.
877 "SELECT ts FROM heartbeat.heartbeat WHERE $whereSQL ORDER BY ts DESC LIMIT 1",
880 $row = $res ?
$res->fetchObject() : false;
882 $this->restoreFlags();
885 return [ $row ?
$row->ts
: null, $nowUnix ];
888 protected function getApproximateLagStatus() {
889 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
890 // Disable caching since this is fast enough and we don't wan't
891 // to be *too* pessimistic by having both the cache TTL and the
892 // pt-heartbeat interval count as lag in getSessionLagStatus()
893 return parent
::getApproximateLagStatus();
896 $key = $this->srvCache
->makeGlobalKey( 'mysql-lag', $this->getServer() );
897 $approxLag = $this->srvCache
->get( $key );
899 $approxLag = parent
::getApproximateLagStatus();
900 $this->srvCache
->set( $key, $approxLag, 1 );
906 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
907 if ( !( $pos instanceof MySQLMasterPos
) ) {
908 throw new InvalidArgumentException( "Position not an instance of MySQLMasterPos" );
911 if ( $this->getLBInfo( 'is static' ) === true ) {
912 return 0; // this is a copy of a read-only dataset with no master DB
913 } elseif ( $this->lastKnownReplicaPos
&& $this->lastKnownReplicaPos
->hasReached( $pos ) ) {
914 return 0; // already reached this point for sure
917 // Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
918 if ( $pos->getGTIDs() ) {
919 // Ignore GTIDs from domains exclusive to the master DB (presumably inactive)
920 $rpos = $this->getReplicaPos();
921 $gtidsWait = $rpos ? MySQLMasterPos
::getCommonDomainGTIDs( $pos, $rpos ) : [];
923 $this->queryLogger
->error(
924 "No GTIDs with the same domain between master ($pos) and replica ($rpos)",
925 $this->getLogContext( [
926 'method' => __METHOD__
,
930 return -1; // $pos is from the wrong cluster?
932 // Wait on the GTID set (MariaDB only)
933 $gtidArg = $this->addQuotes( implode( ',', $gtidsWait ) );
934 $res = $this->doQuery( "SELECT MASTER_GTID_WAIT($gtidArg, $timeout)" );
936 // Wait on the binlog coordinates
937 $encFile = $this->addQuotes( $pos->getLogFile() );
938 $encPos = intval( $pos->pos
[1] );
939 $res = $this->doQuery( "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)" );
942 $row = $res ?
$this->fetchRow( $res ) : false;
944 throw new DBExpectedError( $this,
945 "MASTER_POS_WAIT() or MASTER_GTID_WAIT() failed: {$this->lastError()}" );
948 // Result can be NULL (error), -1 (timeout), or 0+ per the MySQL manual
949 $status = ( $row[0] !== null ) ?
intval( $row[0] ) : null;
950 if ( $status === null ) {
951 if ( !$pos->getGTIDs() ) {
952 // T126436: jobs programmed to wait on master positions might be referencing
953 // binlogs with an old master hostname; this makes MASTER_POS_WAIT() return null.
954 // Try to detect this case and treat the replica DB as having reached the given
955 // position (any master switchover already requires that the new master be caught
956 // up before the switch).
957 $replicationPos = $this->getReplicaPos();
958 if ( $replicationPos && !$replicationPos->channelsMatch( $pos ) ) {
959 $this->lastKnownReplicaPos
= $replicationPos;
963 } elseif ( $status >= 0 ) {
964 // Remember that this position was reached to save queries next time
965 $this->lastKnownReplicaPos
= $pos;
972 * Get the position of the master from SHOW SLAVE STATUS
974 * @return MySQLMasterPos|bool
976 public function getReplicaPos() {
977 $now = microtime( true );
979 if ( $this->useGTIDs
) {
980 $res = $this->query( "SELECT @@global.gtid_slave_pos AS Value", __METHOD__
);
981 $gtidRow = $this->fetchObject( $res );
982 if ( $gtidRow && strlen( $gtidRow->Value
) ) {
983 return new MySQLMasterPos( $gtidRow->Value
, $now );
987 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__
);
988 $row = $this->fetchObject( $res );
989 if ( $row && strlen( $row->Relay_Master_Log_File
) ) {
990 return new MySQLMasterPos(
991 "{$row->Relay_Master_Log_File}/{$row->Exec_Master_Log_Pos}",
1000 * Get the position of the master from SHOW MASTER STATUS
1002 * @return MySQLMasterPos|bool
1004 public function getMasterPos() {
1005 $now = microtime( true );
1007 if ( $this->useGTIDs
) {
1008 $res = $this->query( "SELECT @@global.gtid_binlog_pos AS Value", __METHOD__
);
1009 $gtidRow = $this->fetchObject( $res );
1010 if ( $gtidRow && strlen( $gtidRow->Value
) ) {
1011 return new MySQLMasterPos( $gtidRow->Value
, $now );
1015 $res = $this->query( 'SHOW MASTER STATUS', __METHOD__
);
1016 $row = $this->fetchObject( $res );
1017 if ( $row && strlen( $row->File
) ) {
1018 return new MySQLMasterPos( "{$row->File}/{$row->Position}", $now );
1024 public function serverIsReadOnly() {
1025 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'read_only'", __METHOD__
);
1026 $row = $this->fetchObject( $res );
1028 return $row ?
( strtolower( $row->Value
) === 'on' ) : false;
1032 * @param string $index
1035 function useIndexClause( $index ) {
1036 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
1040 * @param string $index
1043 function ignoreIndexClause( $index ) {
1044 return "IGNORE INDEX (" . $this->indexName( $index ) . ")";
1050 function lowPriorityOption() {
1051 return 'LOW_PRIORITY';
1057 public function getSoftwareLink() {
1058 // MariaDB includes its name in its version string; this is how MariaDB's version of
1059 // the mysql command-line client identifies MariaDB servers (see mariadb_connection()
1060 // in libmysql/libmysql.c).
1061 $version = $this->getServerVersion();
1062 if ( strpos( $version, 'MariaDB' ) !== false ||
strpos( $version, '-maria-' ) !== false ) {
1063 return '[{{int:version-db-mariadb-url}} MariaDB]';
1066 // Percona Server's version suffix is not very distinctive, and @@version_comment
1067 // doesn't give the necessary info for source builds, so assume the server is MySQL.
1068 // (Even Percona's version of mysql doesn't try to make the distinction.)
1069 return '[{{int:version-db-mysql-url}} MySQL]';
1075 public function getServerVersion() {
1076 // Not using mysql_get_server_info() or similar for consistency: in the handshake,
1077 // MariaDB 10 adds the prefix "5.5.5-", and only some newer client libraries strip
1078 // it off (see RPL_VERSION_HACK in include/mysql_com.h).
1079 if ( $this->serverVersion
=== null ) {
1080 $this->serverVersion
= $this->selectField( '', 'VERSION()', '', __METHOD__
);
1082 return $this->serverVersion
;
1086 * @param array $options
1088 public function setSessionOptions( array $options ) {
1089 if ( isset( $options['connTimeout'] ) ) {
1090 $timeout = (int)$options['connTimeout'];
1091 $this->query( "SET net_read_timeout=$timeout" );
1092 $this->query( "SET net_write_timeout=$timeout" );
1097 * @param string &$sql
1098 * @param string &$newLine
1101 public function streamStatementEnd( &$sql, &$newLine ) {
1102 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
1103 preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
1104 $this->delimiter
= $m[1];
1108 return parent
::streamStatementEnd( $sql, $newLine );
1112 * Check to see if a named lock is available. This is non-blocking.
1114 * @param string $lockName Name of lock to poll
1115 * @param string $method Name of method calling us
1119 public function lockIsFree( $lockName, $method ) {
1120 if ( !parent
::lockIsFree( $lockName, $method ) ) {
1121 return false; // already held
1124 $encName = $this->addQuotes( $this->makeLockName( $lockName ) );
1125 $result = $this->query( "SELECT IS_FREE_LOCK($encName) AS lockstatus", $method );
1126 $row = $this->fetchObject( $result );
1128 return ( $row->lockstatus
== 1 );
1132 * @param string $lockName
1133 * @param string $method
1134 * @param int $timeout
1137 public function lock( $lockName, $method, $timeout = 5 ) {
1138 $encName = $this->addQuotes( $this->makeLockName( $lockName ) );
1139 $result = $this->query( "SELECT GET_LOCK($encName, $timeout) AS lockstatus", $method );
1140 $row = $this->fetchObject( $result );
1142 if ( $row->lockstatus
== 1 ) {
1143 parent
::lock( $lockName, $method, $timeout ); // record
1147 $this->queryLogger
->info( __METHOD__
. " failed to acquire lock '{lockname}'",
1148 [ 'lockname' => $lockName ] );
1155 * https://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
1156 * @param string $lockName
1157 * @param string $method
1160 public function unlock( $lockName, $method ) {
1161 $encName = $this->addQuotes( $this->makeLockName( $lockName ) );
1162 $result = $this->query( "SELECT RELEASE_LOCK($encName) as lockstatus", $method );
1163 $row = $this->fetchObject( $result );
1165 if ( $row->lockstatus
== 1 ) {
1166 parent
::unlock( $lockName, $method ); // record
1170 $this->queryLogger
->warning( __METHOD__
. " failed to release lock '$lockName'\n" );
1175 private function makeLockName( $lockName ) {
1176 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1177 // Newer version enforce a 64 char length limit.
1178 return ( strlen( $lockName ) > 64 ) ?
sha1( $lockName ) : $lockName;
1181 public function namedLocksEnqueue() {
1185 public function tableLocksHaveTransactionScope() {
1186 return false; // tied to TCP connection
1189 protected function doLockTables( array $read, array $write, $method ) {
1191 foreach ( $write as $table ) {
1192 $items[] = $this->tableName( $table ) . ' WRITE';
1194 foreach ( $read as $table ) {
1195 $items[] = $this->tableName( $table ) . ' READ';
1198 $sql = "LOCK TABLES " . implode( ',', $items );
1199 $this->query( $sql, $method );
1204 protected function doUnlockTables( $method ) {
1205 $this->query( "UNLOCK TABLES", $method );
1211 * @param bool $value
1213 public function setBigSelects( $value = true ) {
1214 if ( $value === 'default' ) {
1215 if ( $this->defaultBigSelects
=== null ) {
1216 # Function hasn't been called before so it must already be set to the default
1219 $value = $this->defaultBigSelects
;
1221 } elseif ( $this->defaultBigSelects
=== null ) {
1222 $this->defaultBigSelects
=
1223 (bool)$this->selectField( false, '@@sql_big_selects', '', __METHOD__
);
1225 $encValue = $value ?
'1' : '0';
1226 $this->query( "SET sql_big_selects=$encValue", __METHOD__
);
1230 * DELETE where the condition is a join. MySql uses multi-table deletes.
1231 * @param string $delTable
1232 * @param string $joinTable
1233 * @param string $delVar
1234 * @param string $joinVar
1235 * @param array|string $conds
1236 * @param bool|string $fname
1237 * @throws DBUnexpectedError
1238 * @return bool|ResultWrapper
1240 public function deleteJoin(
1241 $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__
1244 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
1247 $delTable = $this->tableName( $delTable );
1248 $joinTable = $this->tableName( $joinTable );
1249 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1251 if ( $conds != '*' ) {
1252 $sql .= ' AND ' . $this->makeList( $conds, self
::LIST_AND
);
1255 return $this->query( $sql, $fname );
1259 * @param string $table
1260 * @param array $rows
1261 * @param array $uniqueIndexes
1263 * @param string $fname
1266 public function upsert( $table, array $rows, array $uniqueIndexes,
1267 array $set, $fname = __METHOD__
1269 if ( !count( $rows ) ) {
1270 return true; // nothing to do
1273 if ( !is_array( reset( $rows ) ) ) {
1277 $table = $this->tableName( $table );
1278 $columns = array_keys( $rows[0] );
1280 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
1282 foreach ( $rows as $row ) {
1283 $rowTuples[] = '(' . $this->makeList( $row ) . ')';
1285 $sql .= implode( ',', $rowTuples );
1286 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, self
::LIST_SET
);
1288 return (bool)$this->query( $sql, $fname );
1292 * Determines how long the server has been up
1296 public function getServerUptime() {
1297 $vars = $this->getMysqlStatus( 'Uptime' );
1299 return (int)$vars['Uptime'];
1303 * Determines if the last failure was due to a deadlock
1307 public function wasDeadlock() {
1308 return $this->lastErrno() == 1213;
1312 * Determines if the last failure was due to a lock timeout
1316 public function wasLockTimeout() {
1317 return $this->lastErrno() == 1205;
1321 * Determines if the last failure was due to the database being read-only.
1325 public function wasReadOnlyError() {
1326 return $this->lastErrno() == 1223 ||
1327 ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
1330 public function wasConnectionError( $errno ) {
1331 return $errno == 2013 ||
$errno == 2006;
1335 * @param string $oldName
1336 * @param string $newName
1337 * @param bool $temporary
1338 * @param string $fname
1341 public function duplicateTableStructure(
1342 $oldName, $newName, $temporary = false, $fname = __METHOD__
1344 $tmp = $temporary ?
'TEMPORARY ' : '';
1345 $newName = $this->addIdentifierQuotes( $newName );
1346 $oldName = $this->addIdentifierQuotes( $oldName );
1347 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
1349 return $this->query( $query, $fname );
1353 * List all tables on the database
1355 * @param string $prefix Only show tables with this prefix, e.g. mw_
1356 * @param string $fname Calling function name
1359 public function listTables( $prefix = null, $fname = __METHOD__
) {
1360 $result = $this->query( "SHOW TABLES", $fname );
1364 foreach ( $result as $table ) {
1365 $vars = get_object_vars( $table );
1366 $table = array_pop( $vars );
1368 if ( !$prefix ||
strpos( $table, $prefix ) === 0 ) {
1369 $endArray[] = $table;
1377 * @param string $tableName
1378 * @param string $fName
1379 * @return bool|ResultWrapper
1381 public function dropTable( $tableName, $fName = __METHOD__
) {
1382 if ( !$this->tableExists( $tableName, $fName ) ) {
1386 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1390 * Get status information from SHOW STATUS in an associative array
1392 * @param string $which
1395 private function getMysqlStatus( $which = "%" ) {
1396 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1399 foreach ( $res as $row ) {
1400 $status[$row->Variable_name
] = $row->Value
;
1407 * Lists VIEWs in the database
1409 * @param string $prefix Only show VIEWs with this prefix, eg.
1410 * unit_test_, or $wgDBprefix. Default: null, would return all views.
1411 * @param string $fname Name of calling function
1415 public function listViews( $prefix = null, $fname = __METHOD__
) {
1416 // The name of the column containing the name of the VIEW
1417 $propertyName = 'Tables_in_' . $this->dbName
;
1419 // Query for the VIEWS
1420 $res = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1422 foreach ( $res as $row ) {
1423 array_push( $allViews, $row->$propertyName );
1426 if ( is_null( $prefix ) ||
$prefix === '' ) {
1430 $filteredViews = [];
1431 foreach ( $allViews as $viewName ) {
1432 // Does the name of this VIEW start with the table-prefix?
1433 if ( strpos( $viewName, $prefix ) === 0 ) {
1434 array_push( $filteredViews, $viewName );
1438 return $filteredViews;
1442 * Differentiates between a TABLE and a VIEW.
1444 * @param string $name Name of the TABLE/VIEW to test
1445 * @param string $prefix
1449 public function isView( $name, $prefix = null ) {
1450 return in_array( $name, $this->listViews( $prefix ) );
1453 protected function isTransactableQuery( $sql ) {
1454 return parent
::isTransactableQuery( $sql ) &&
1455 !preg_match( '/^SELECT\s+(GET|RELEASE|IS_FREE)_LOCK\(/', $sql );
1459 * @param string $field Field or column to cast
1462 public function buildIntegerCast( $field ) {
1463 return 'CAST( ' . $field . ' AS SIGNED )';
1468 class_alias( DatabaseMysqlBase
::class, 'DatabaseMysqlBase' );