/** @var TransactionProfiler */
protected $trxProfiler;
- /**
- * A string describing the current software version, and possibly
- * other details in a user-friendly way. Will be listed on Special:Version, etc.
- * Use getServerVersion() to get machine-friendly information.
- *
- * @return string Version information from the database server
- */
public function getServerInfo() {
return $this->getServerVersion();
}
return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
}
- /**
- * Turns buffering of SQL result sets on (true) or off (false). Default is
- * "on".
- *
- * Unbuffered queries are very troublesome in MySQL:
- *
- * - If another query is executed while the first query is being read
- * out, the first query is killed. This means you can't call normal
- * MediaWiki functions while you are reading an unbuffered query result
- * from a normal wfGetDB() connection.
- *
- * - Unbuffered queries cause the MySQL server to use large amounts of
- * memory and to hold broad locks which block other queries.
- *
- * If you want to limit client-side memory, it's almost always better to
- * split up queries into batches using a LIMIT clause than to switch off
- * buffering.
- *
- * @param null|bool $buffer
- * @return null|bool The previous value of the flag
- */
public function bufferResults( $buffer = null ) {
if ( is_null( $buffer ) ) {
return !(bool)( $this->mFlags & DBO_NOBUFFER );
return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors );
}
- /**
- * Gets the current transaction level.
- *
- * Historically, transactions were allowed to be "nested". This is no
- * longer supported, so this function really only returns a boolean.
- *
- * @return int The previous value
- */
public function trxLevel() {
return $this->mTrxLevel;
}
- /**
- * Get the UNIX timestamp of the time that the transaction was established
- *
- * This can be used to reason about the staleness of SELECT data
- * in REPEATABLE-READ transaction isolation level.
- *
- * @return float|null Returns null if there is not active transaction
- * @since 1.25
- */
public function trxTimestamp() {
return $this->mTrxLevel ? $this->mTrxTimestamp : null;
}
- /**
- * Get/set the table prefix.
- * @param string $prefix The table prefix to set, or omitted to leave it unchanged.
- * @return string The previous table prefix.
- */
public function tablePrefix( $prefix = null ) {
return wfSetVar( $this->mTablePrefix, $prefix );
}
- /**
- * Get/set the db schema.
- * @param string $schema The database schema to set, or omitted to leave it unchanged.
- * @return string The previous db schema.
- */
public function dbSchema( $schema = null ) {
return wfSetVar( $this->mSchema, $schema );
}
$this->fileHandle = $fh;
}
- /**
- * Get properties passed down from the server info array of the load
- * balancer.
- *
- * @param string $name The entry of the info array to get, or null to get the
- * whole array
- *
- * @return array|mixed|null
- */
public function getLBInfo( $name = null ) {
if ( is_null( $name ) ) {
return $this->mLBInfo;
}
}
- /**
- * Set the LB info array, or a member of it. If called with one parameter,
- * the LB info array is set to that parameter. If it is called with two
- * parameters, the member with the given name is set to the given value.
- *
- * @param string $name
- * @param array $value
- */
public function setLBInfo( $name, $value = null ) {
if ( is_null( $value ) ) {
$this->mLBInfo = $name;
return false;
}
- /**
- * Returns true if this database does an implicit sort when doing GROUP BY
- *
- * @return bool
- */
public function implicitGroupby() {
return true;
}
- /**
- * Returns true if this database does an implicit order by when the column has an index
- * For example: SELECT page_title FROM page LIMIT 1
- *
- * @return bool
- */
public function implicitOrderby() {
return true;
}
return false;
}
- /**
- * Return the last query that went through DatabaseBase::query()
- * @return string
- */
public function lastQuery() {
return $this->mLastQuery;
}
- /**
- * Returns true if the connection may have been used for write queries.
- * Should return true if unsure.
- *
- * @return bool
- */
public function doneWrites() {
return (bool)$this->mDoneWrites;
}
- /**
- * Returns the last time the connection may have been used for write queries.
- * Should return a timestamp if unsure.
- *
- * @return int|float UNIX timestamp or false
- * @since 1.24
- */
public function lastDoneWrites() {
return $this->mDoneWrites ?: false;
}
- /**
- * @return bool Whether there is a transaction open with possible write queries
- * @since 1.27
- */
public function writesPending() {
return $this->mTrxLevel && $this->mTrxDoneWrites;
}
- /**
- * Returns true if there is a transaction open with possible write
- * queries or transaction pre-commit/idle callbacks waiting on it to finish.
- *
- * @return bool
- */
public function writesOrCallbacksPending() {
return $this->mTrxLevel && (
$this->mTrxDoneWrites || $this->mTrxIdleCallbacks || $this->mTrxPreCommitCallbacks
);
}
- /**
- * Get the time spend running write queries for this
- *
- * High times could be due to scanning, updates, locking, and such
- *
- * @return float|bool Returns false if not transaction is active
- * @since 1.26
- */
public function pendingWriteQueryDuration() {
return $this->mTrxLevel ? $this->mTrxWriteDuration : false;
}
- /**
- * Is a connection to the database open?
- * @return bool
- */
public function isOpen() {
return $this->mOpened;
}
- /**
- * Set a flag for this connection
- *
- * @param int $flag DBO_* constants from Defines.php:
- * - DBO_DEBUG: output some debug info (same as debug())
- * - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
- * - DBO_TRX: automatically start transactions
- * - DBO_DEFAULT: automatically sets DBO_TRX if not in command line mode
- * and removes it in command line mode
- * - DBO_PERSISTENT: use persistant database connection
- */
public function setFlag( $flag ) {
$this->mFlags |= $flag;
}
- /**
- * Clear a flag for this connection
- *
- * @param int $flag DBO_* constants from Defines.php:
- * - DBO_DEBUG: output some debug info (same as debug())
- * - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
- * - DBO_TRX: automatically start transactions
- * - DBO_DEFAULT: automatically sets DBO_TRX if not in command line mode
- * and removes it in command line mode
- * - DBO_PERSISTENT: use persistant database connection
- */
public function clearFlag( $flag ) {
$this->mFlags &= ~$flag;
}
- /**
- * Returns a boolean whether the flag $flag is set for this connection
- *
- * @param int $flag DBO_* constants from Defines.php:
- * - DBO_DEBUG: output some debug info (same as debug())
- * - DBO_NOBUFFER: don't buffer results (inverse of bufferResults())
- * - DBO_TRX: automatically start transactions
- * - DBO_PERSISTENT: use persistant database connection
- * @return bool
- */
public function getFlag( $flag ) {
return !!( $this->mFlags & $flag );
}
- /**
- * General read-only accessor
- *
- * @param string $name
- * @return string
- */
public function getProperty( $name ) {
return $this->$name;
}
- /**
- * @return string
- */
public function getWikiID() {
if ( $this->mTablePrefix ) {
return "{$this->mDBname}-{$this->mTablePrefix}";
);
}
- /**
- * Closes a database connection.
- * if it is open : commits any open transactions
- *
- * @throws MWException
- * @return bool Operation success. true if already closed.
- */
public function close() {
if ( count( $this->mTrxIdleCallbacks ) ) { // sanity
throw new MWException( "Transaction idle callbacks still pending." );
*/
abstract protected function closeConnection();
- /**
- * @param string $error Fallback error message, used if none is given by DB
- * @throws DBConnectionError
- */
function reportConnectionError( $error = 'Unknown error' ) {
$myError = $this->lastError();
if ( $myError ) {
return !in_array( $verb, array( 'BEGIN', 'COMMIT', 'ROLLBACK', 'SHOW', 'SET' ) );
}
- /**
- * Run an SQL query and return the result. Normally throws a DBQueryError
- * on failure. If errors are ignored, returns false instead.
- *
- * In new code, the query wrappers select(), insert(), update(), delete(),
- * etc. should be used where possible, since they give much better DBMS
- * independence and automatically quote or validate user input in a variety
- * of contexts. This function is generally only useful for queries which are
- * explicitly DBMS-dependent and are unsupported by the query wrappers, such
- * as CREATE TABLE.
- *
- * However, the query wrappers themselves should call this function.
- *
- * @param string $sql SQL query
- * @param string $fname Name of the calling function, for profiling/SHOW PROCESSLIST
- * comment (you can use __METHOD__ or add some extra info)
- * @param bool $tempIgnore Whether to avoid throwing an exception on errors...
- * maybe best to catch the exception instead?
- * @throws MWException
- * @return bool|ResultWrapper True for a successful write query, ResultWrapper object
- * for a successful read query, or false on failure if $tempIgnore set
- */
public function query( $sql, $fname = __METHOD__, $tempIgnore = false ) {
global $wgUser;
return $res;
}
- /**
- * Report a query error. Log the error, and if neither the object ignore
- * flag nor the $tempIgnore flag is set, throw a DBQueryError.
- *
- * @param string $error
- * @param int $errno
- * @param string $sql
- * @param string $fname
- * @param bool $tempIgnore
- * @throws DBQueryError
- */
public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
if ( $this->ignoreErrors() || $tempIgnore ) {
wfDebug( "SQL ERROR (ignored): $error\n" );
}
}
- /**
- * Free a result object returned by query() or select(). It's usually not
- * necessary to call this, just use unset() or let the variable holding
- * the result object go out of scope.
- *
- * @param mixed $res A SQL result
- */
public function freeResult( $res ) {
}
- /**
- * A SELECT wrapper which returns a single field from a single result row.
- *
- * Usually throws a DBQueryError on failure. If errors are explicitly
- * ignored, returns false on failure.
- *
- * If no result rows are returned from the query, false is returned.
- *
- * @param string|array $table Table name. See DatabaseBase::select() for details.
- * @param string $var The field name to select. This must be a valid SQL
- * fragment: do not use unvalidated user input.
- * @param string|array $cond The condition array. See DatabaseBase::select() for details.
- * @param string $fname The function name of the caller.
- * @param string|array $options The query options. See DatabaseBase::select() for details.
- *
- * @return bool|mixed The value from the field, or false on failure.
- * @throws DBUnexpectedError
- */
public function selectField(
$table, $var, $cond = '', $fname = __METHOD__, $options = array()
) {
}
}
- /**
- * A SELECT wrapper which returns a list of single field values from result rows.
- *
- * Usually throws a DBQueryError on failure. If errors are explicitly
- * ignored, returns false on failure.
- *
- * If no result rows are returned from the query, false is returned.
- *
- * @param string|array $table Table name. See DatabaseBase::select() for details.
- * @param string $var The field name to select. This must be a valid SQL
- * fragment: do not use unvalidated user input.
- * @param string|array $cond The condition array. See DatabaseBase::select() for details.
- * @param string $fname The function name of the caller.
- * @param string|array $options The query options. See DatabaseBase::select() for details.
- * @param string|array $join_conds The join conditions. See DatabaseBase::select() for details.
- *
- * @return bool|array The values from the field, or false on failure
- * @throws DBUnexpectedError
- * @since 1.25
- */
public function selectFieldValues(
$table, $var, $cond = '', $fname = __METHOD__, $options = array(), $join_conds = array()
) {
return '';
}
- /**
- * Execute a SELECT query constructed using the various parameters provided.
- * See below for full details of the parameters.
- *
- * @param string|array $table Table name
- * @param string|array $vars Field names
- * @param string|array $conds Conditions
- * @param string $fname Caller function name
- * @param array $options Query options
- * @param array $join_conds Join conditions
- *
- *
- * @param string|array $table
- *
- * May be either an array of table names, or a single string holding a table
- * name. If an array is given, table aliases can be specified, for example:
- *
- * array( 'a' => 'user' )
- *
- * This includes the user table in the query, with the alias "a" available
- * for use in field names (e.g. a.user_name).
- *
- * All of the table names given here are automatically run through
- * DatabaseBase::tableName(), which causes the table prefix (if any) to be
- * added, and various other table name mappings to be performed.
- *
- *
- * @param string|array $vars
- *
- * May be either a field name or an array of field names. The field names
- * can be complete fragments of SQL, for direct inclusion into the SELECT
- * query. If an array is given, field aliases can be specified, for example:
- *
- * array( 'maxrev' => 'MAX(rev_id)' )
- *
- * This includes an expression with the alias "maxrev" in the query.
- *
- * If an expression is given, care must be taken to ensure that it is
- * DBMS-independent.
- *
- *
- * @param string|array $conds
- *
- * May be either a string containing a single condition, or an array of
- * conditions. If an array is given, the conditions constructed from each
- * element are combined with AND.
- *
- * Array elements may take one of two forms:
- *
- * - Elements with a numeric key are interpreted as raw SQL fragments.
- * - Elements with a string key are interpreted as equality conditions,
- * where the key is the field name.
- * - If the value of such an array element is a scalar (such as a
- * string), it will be treated as data and thus quoted appropriately.
- * If it is null, an IS NULL clause will be added.
- * - If the value is an array, an IN (...) clause will be constructed
- * from its non-null elements, and an IS NULL clause will be added
- * if null is present, such that the field may match any of the
- * elements in the array. The non-null elements will be quoted.
- *
- * Note that expressions are often DBMS-dependent in their syntax.
- * DBMS-independent wrappers are provided for constructing several types of
- * expression commonly used in condition queries. See:
- * - DatabaseBase::buildLike()
- * - DatabaseBase::conditional()
- *
- *
- * @param string|array $options
- *
- * Optional: Array of query options. Boolean options are specified by
- * including them in the array as a string value with a numeric key, for
- * example:
- *
- * array( 'FOR UPDATE' )
- *
- * The supported options are:
- *
- * - OFFSET: Skip this many rows at the start of the result set. OFFSET
- * with LIMIT can theoretically be used for paging through a result set,
- * but this is discouraged in MediaWiki for performance reasons.
- *
- * - LIMIT: Integer: return at most this many rows. The rows are sorted
- * and then the first rows are taken until the limit is reached. LIMIT
- * is applied to a result set after OFFSET.
- *
- * - FOR UPDATE: Boolean: lock the returned rows so that they can't be
- * changed until the next COMMIT.
- *
- * - DISTINCT: Boolean: return only unique result rows.
- *
- * - GROUP BY: May be either an SQL fragment string naming a field or
- * expression to group by, or an array of such SQL fragments.
- *
- * - HAVING: May be either an string containing a HAVING clause or an array of
- * conditions building the HAVING clause. If an array is given, the conditions
- * constructed from each element are combined with AND.
- *
- * - ORDER BY: May be either an SQL fragment giving a field name or
- * expression to order by, or an array of such SQL fragments.
- *
- * - USE INDEX: This may be either a string giving the index name to use
- * for the query, or an array. If it is an associative array, each key
- * gives the table name (or alias), each value gives the index name to
- * use for that table. All strings are SQL fragments and so should be
- * validated by the caller.
- *
- * - EXPLAIN: In MySQL, this causes an EXPLAIN SELECT query to be run,
- * instead of SELECT.
- *
- * And also the following boolean MySQL extensions, see the MySQL manual
- * for documentation:
- *
- * - LOCK IN SHARE MODE
- * - STRAIGHT_JOIN
- * - HIGH_PRIORITY
- * - SQL_BIG_RESULT
- * - SQL_BUFFER_RESULT
- * - SQL_SMALL_RESULT
- * - SQL_CALC_FOUND_ROWS
- * - SQL_CACHE
- * - SQL_NO_CACHE
- *
- *
- * @param string|array $join_conds
- *
- * Optional associative array of table-specific join conditions. In the
- * most common case, this is unnecessary, since the join condition can be
- * in $conds. However, it is useful for doing a LEFT JOIN.
- *
- * The key of the array contains the table name or alias. The value is an
- * array with two elements, numbered 0 and 1. The first gives the type of
- * join, the second is an SQL fragment giving the join condition for that
- * table. For example:
- *
- * array( 'page' => array( 'LEFT JOIN', 'page_latest=rev_id' ) )
- *
- * @return ResultWrapper|bool If the query returned no rows, a ResultWrapper
- * with no rows in it will be returned. If there was a query error, a
- * DBQueryError exception will be thrown, except if the "ignore errors"
- * option was set, in which case false will be returned.
- */
public function select( $table, $vars, $conds = '', $fname = __METHOD__,
$options = array(), $join_conds = array() ) {
$sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
return $this->query( $sql, $fname );
}
- /**
- * The equivalent of DatabaseBase::select() except that the constructed SQL
- * is returned, instead of being immediately executed. This can be useful for
- * doing UNION queries, where the SQL text of each query is needed. In general,
- * however, callers outside of Database classes should just use select().
- *
- * @param string|array $table Table name
- * @param string|array $vars Field names
- * @param string|array $conds Conditions
- * @param string $fname Caller function name
- * @param string|array $options Query options
- * @param string|array $join_conds Join conditions
- *
- * @return string SQL query string.
- * @see DatabaseBase::select()
- */
public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__,
$options = array(), $join_conds = array()
) {
return $sql;
}
- /**
- * Single row SELECT wrapper. Equivalent to DatabaseBase::select(), except
- * that a single row object is returned. If the query returns no rows,
- * false is returned.
- *
- * @param string|array $table Table name
- * @param string|array $vars Field names
- * @param array $conds Conditions
- * @param string $fname Caller function name
- * @param string|array $options Query options
- * @param array|string $join_conds Join conditions
- *
- * @return stdClass|bool
- */
public function selectRow( $table, $vars, $conds, $fname = __METHOD__,
$options = array(), $join_conds = array()
) {
return $obj;
}
- /**
- * Estimate the number of rows in dataset
- *
- * MySQL allows you to estimate the number of rows that would be returned
- * by a SELECT query, using EXPLAIN SELECT. The estimate is provided using
- * index cardinality statistics, and is notoriously inaccurate, especially
- * when large numbers of rows have recently been added or deleted.
- *
- * For DBMSs that don't support fast result size estimation, this function
- * will actually perform the SELECT COUNT(*).
- *
- * Takes the same arguments as DatabaseBase::select().
- *
- * @param string $table Table name
- * @param string $vars Unused
- * @param array|string $conds Filters on the table
- * @param string $fname Function name for profiling
- * @param array $options Options for select
- * @return int Row count
- */
public function estimateRowCount(
$table, $vars = '*', $conds = '', $fname = __METHOD__, $options = array()
) {
return $rows;
}
- /**
- * Get the number of rows in dataset
- *
- * This is useful when trying to do COUNT(*) but with a LIMIT for performance.
- *
- * Takes the same arguments as DatabaseBase::select().
- *
- * @since 1.27 Added $join_conds parameter
- *
- * @param array|string $tables Table names
- * @param string $vars Unused
- * @param array|string $conds Filters on the table
- * @param string $fname Function name for profiling
- * @param array $options Options for select
- * @param array $join_conds Join conditions (since 1.27)
- * @return int Row count
- */
public function selectRowCount(
$tables, $vars = '*', $conds = '', $fname = __METHOD__, $options = array(), $join_conds = array()
) {
return $sql;
}
- /**
- * Determines whether a field exists in a table
- *
- * @param string $table Table name
- * @param string $field Filed to check on that table
- * @param string $fname Calling function name (optional)
- * @return bool Whether $table has filed $field
- */
public function fieldExists( $table, $field, $fname = __METHOD__ ) {
$info = $this->fieldInfo( $table, $field );
return (bool)$info;
}
- /**
- * Determines whether an index exists
- * Usually throws a DBQueryError on failure
- * If errors are explicitly ignored, returns NULL on failure
- *
- * @param string $table
- * @param string $index
- * @param string $fname
- * @return bool|null
- */
public function indexExists( $table, $index, $fname = __METHOD__ ) {
if ( !$this->tableExists( $table ) ) {
return null;
}
}
- /**
- * Query whether a given table exists
- *
- * @param string $table
- * @param string $fname
- * @return bool
- */
public function tableExists( $table, $fname = __METHOD__ ) {
$table = $this->tableName( $table );
$old = $this->ignoreErrors( true );
return (bool)$res;
}
- /**
- * Determines if a given index is unique
- *
- * @param string $table
- * @param string $index
- *
- * @return bool
- */
public function indexUnique( $table, $index ) {
$indexInfo = $this->indexInfo( $table, $index );
return implode( ' ', $options );
}
- /**
- * INSERT wrapper, inserts an array into a table.
- *
- * $a may be either:
- *
- * - A single associative array. The array keys are the field names, and
- * the values are the values to insert. The values are treated as data
- * and will be quoted appropriately. If NULL is inserted, this will be
- * converted to a database NULL.
- * - An array with numeric keys, holding a list of associative arrays.
- * This causes a multi-row INSERT on DBMSs that support it. The keys in
- * each subarray must be identical to each other, and in the same order.
- *
- * $options is an array of options, with boolean options encoded as values
- * with numeric keys, in the same style as $options in
- * DatabaseBase::select(). Supported options are:
- *
- * - IGNORE: Boolean: if present, duplicate key errors are ignored, and
- * any rows which cause duplicate key errors are not inserted. It's
- * possible to determine how many rows were successfully inserted using
- * DatabaseBase::affectedRows().
- *
- * @param string $table Table name. This will be passed through
- * DatabaseBase::tableName().
- * @param array $a Array of rows to insert
- * @param string $fname Calling function name (use __METHOD__) for logs/profiling
- * @param array $options Array of options
- *
- * @throws DBQueryError Usually throws a DBQueryError on failure. If errors are explicitly ignored,
- * returns success.
- *
- * @return bool
- */
public function insert( $table, $a, $fname = __METHOD__, $options = array() ) {
# No rows to insert, easy just return now
if ( !count( $a ) ) {
return implode( ' ', $opts );
}
- /**
- * UPDATE wrapper. Takes a condition array and a SET array.
- *
- * @param string $table Name of the table to UPDATE. This will be passed through
- * DatabaseBase::tableName().
- * @param array $values An array of values to SET. For each array element,
- * the key gives the field name, and the value gives the data to set
- * that field to. The data will be quoted by DatabaseBase::addQuotes().
- * @param array $conds An array of conditions (WHERE). See
- * DatabaseBase::select() for the details of the format of condition
- * arrays. Use '*' to update all rows.
- * @param string $fname The function name of the caller (from __METHOD__),
- * for logging and profiling.
- * @param array $options An array of UPDATE options, can be:
- * - IGNORE: Ignore unique key conflicts
- * - LOW_PRIORITY: MySQL-specific, see MySQL manual.
- * @return bool
- */
function update( $table, $values, $conds, $fname = __METHOD__, $options = array() ) {
$table = $this->tableName( $table );
$opts = $this->makeUpdateOptions( $options );
return $this->query( $sql, $fname );
}
- /**
- * Makes an encoded list of strings from an array
- *
- * @param array $a Containing the data
- * @param int $mode Constant
- * - LIST_COMMA: Comma separated, no field names
- * - LIST_AND: ANDed WHERE clause (without the WHERE). See the
- * documentation for $conds in DatabaseBase::select().
- * - LIST_OR: ORed WHERE clause (without the WHERE)
- * - LIST_SET: Comma separated with field names, like a SET clause
- * - LIST_NAMES: Comma separated field names
- * @throws MWException|DBUnexpectedError
- * @return string
- */
public function makeList( $a, $mode = LIST_COMMA ) {
if ( !is_array( $a ) ) {
throw new DBUnexpectedError( $this, 'DatabaseBase::makeList called with incorrect parameters' );
return $list;
}
- /**
- * Build a partial where clause from a 2-d array such as used for LinkBatch.
- * The keys on each level may be either integers or strings.
- *
- * @param array $data Organized as 2-d
- * array(baseKeyVal => array(subKeyVal => [ignored], ...), ...)
- * @param string $baseKey Field name to match the base-level keys to (eg 'pl_namespace')
- * @param string $subKey Field name to match the sub-level keys to (eg 'pl_title')
- * @return string|bool SQL fragment, or false if no items in array
- */
public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
$conds = array();
return $valuename;
}
- /**
- * @param string $field
- * @return string
- */
public function bitNot( $field ) {
return "(~$field)";
}
- /**
- * @param string $fieldLeft
- * @param string $fieldRight
- * @return string
- */
public function bitAnd( $fieldLeft, $fieldRight ) {
return "($fieldLeft & $fieldRight)";
}
- /**
- * @param string $fieldLeft
- * @param string $fieldRight
- * @return string
- */
public function bitOr( $fieldLeft, $fieldRight ) {
return "($fieldLeft | $fieldRight)";
}
- /**
- * Build a concatenation list to feed into a SQL query
- * @param array $stringList List of raw SQL expressions; caller is
- * responsible for any quoting
- * @return string
- */
public function buildConcat( $stringList ) {
return 'CONCAT(' . implode( ',', $stringList ) . ')';
}
- /**
- * Build a GROUP_CONCAT or equivalent statement for a query.
- *
- * This is useful for combining a field for several rows into a single string.
- * NULL values will not appear in the output, duplicated values will appear,
- * and the resulting delimiter-separated values have no defined sort order.
- * Code using the results may need to use the PHP unique() or sort() methods.
- *
- * @param string $delim Glue to bind the results together
- * @param string|array $table Table name
- * @param string $field Field name
- * @param string|array $conds Conditions
- * @param string|array $join_conds Join conditions
- * @return string SQL text
- * @since 1.23
- */
public function buildGroupConcatField(
$delim, $table, $field, $conds = '', $join_conds = array()
) {
return '(' . $this->selectSQLText( $table, $fld, $conds, null, array(), $join_conds ) . ')';
}
- /**
- * Change the current database
- *
- * @todo Explain what exactly will fail if this is not overridden.
- *
- * @param string $db
- *
- * @return bool Success or failure
- */
public function selectDB( $db ) {
# Stub. Shouldn't cause serious problems if it's not overridden, but
# if your database engine supports a concept similar to MySQL's
return true;
}
- /**
- * Get the current DB name
- * @return string
- */
public function getDBname() {
return $this->mDBname;
}
- /**
- * Get the server hostname or IP address
- * @return string
- */
public function getServer() {
return $this->mServer;
}
}
}
- /**
- * Adds quotes and backslashes.
- *
- * @param string|Blob $s
- * @return string
- */
public function addQuotes( $s ) {
if ( $s instanceof Blob ) {
$s = $s->fetch();
return addcslashes( $s, '\%_' );
}
- /**
- * LIKE statement wrapper, receives a variable-length argument list with
- * parts of pattern to match containing either string literals that will be
- * escaped or tokens returned by anyChar() or anyString(). Alternatively,
- * the function could be provided with an array of aforementioned
- * parameters.
- *
- * Example: $dbr->buildLike( 'My_page_title/', $dbr->anyString() ) returns
- * a LIKE clause that searches for subpages of 'My page title'.
- * Alternatively:
- * $pattern = array( 'My_page_title/', $dbr->anyString() );
- * $query .= $dbr->buildLike( $pattern );
- *
- * @since 1.16
- * @return string Fully built LIKE statement
- */
public function buildLike() {
$params = func_get_args();
return " LIKE {$this->addQuotes( $s )} ";
}
- /**
- * Returns a token for buildLike() that denotes a '_' to be used in a LIKE query
- *
- * @return LikeMatch
- */
public function anyChar() {
return new LikeMatch( '_' );
}
- /**
- * Returns a token for buildLike() that denotes a '%' to be used in a LIKE query
- *
- * @return LikeMatch
- */
public function anyString() {
return new LikeMatch( '%' );
}
- /**
- * Returns an appropriately quoted sequence value for inserting a new row.
- * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL
- * subclass will return an integer, and save the value for insertId()
- *
- * Any implementation of this function should *not* involve reusing
- * sequence numbers created for rolled-back transactions.
- * See http://bugs.mysql.com/bug.php?id=30767 for details.
- * @param string $seqName
- * @return null|int
- */
public function nextSequenceValue( $seqName ) {
return null;
}
return '';
}
- /**
- * REPLACE query wrapper.
- *
- * REPLACE is a very handy MySQL extension, which functions like an INSERT
- * except that when there is a duplicate key error, the old row is deleted
- * and the new row is inserted in its place.
- *
- * We simulate this with standard SQL with a DELETE followed by INSERT. To
- * perform the delete, we need to know what the unique indexes are so that
- * we know how to find the conflicting rows.
- *
- * It may be more efficient to leave off unique indexes which are unlikely
- * to collide. However if you do this, you run the risk of encountering
- * errors which wouldn't have occurred in MySQL.
- *
- * @param string $table The table to replace the row(s) in.
- * @param array $uniqueIndexes Is an array of indexes. Each element may be either
- * a field name or an array of field names
- * @param array $rows Can be either a single row to insert, or multiple rows,
- * in the same format as for DatabaseBase::insert()
- * @param string $fname Calling function name (use __METHOD__) for logs/profiling
- */
public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
$quotedTable = $this->tableName( $table );
return $this->query( $sql, $fname );
}
- /**
- * INSERT ON DUPLICATE KEY UPDATE wrapper, upserts an array into a table.
- *
- * This updates any conflicting rows (according to the unique indexes) using
- * the provided SET clause and inserts any remaining (non-conflicted) rows.
- *
- * $rows may be either:
- * - A single associative array. The array keys are the field names, and
- * the values are the values to insert. The values are treated as data
- * and will be quoted appropriately. If NULL is inserted, this will be
- * converted to a database NULL.
- * - An array with numeric keys, holding a list of associative arrays.
- * This causes a multi-row INSERT on DBMSs that support it. The keys in
- * each subarray must be identical to each other, and in the same order.
- *
- * It may be more efficient to leave off unique indexes which are unlikely
- * to collide. However if you do this, you run the risk of encountering
- * errors which wouldn't have occurred in MySQL.
- *
- * Usually throws a DBQueryError on failure. If errors are explicitly ignored,
- * returns success.
- *
- * @since 1.22
- *
- * @param string $table Table name. This will be passed through DatabaseBase::tableName().
- * @param array $rows A single row or list of rows to insert
- * @param array $uniqueIndexes List of single field names or field name tuples
- * @param array $set An array of values to SET. For each array element, the
- * key gives the field name, and the value gives the data to set that
- * field to. The data will be quoted by DatabaseBase::addQuotes().
- * @param string $fname Calling function name (use __METHOD__) for logs/profiling
- * @throws Exception
- * @return bool
- */
public function upsert( $table, array $rows, array $uniqueIndexes, array $set,
$fname = __METHOD__
) {
return $ok;
}
- /**
- * DELETE where the condition is a join.
- *
- * MySQL overrides this to use a multi-table DELETE syntax, in other databases
- * we use sub-selects
- *
- * For safety, an empty $conds will not delete everything. If you want to
- * delete all rows where the join condition matches, set $conds='*'.
- *
- * DO NOT put the join condition in $conds.
- *
- * @param string $delTable The table to delete from.
- * @param string $joinTable The other table.
- * @param string $delVar The variable to join on, in the first table.
- * @param string $joinVar The variable to join on, in the second table.
- * @param array $conds Condition array of field names mapped to variables,
- * ANDed together in the WHERE clause
- * @param string $fname Calling function name (use __METHOD__) for logs/profiling
- * @throws DBUnexpectedError
- */
public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
$fname = __METHOD__
) {
return '';
}
- /**
- * DELETE query wrapper.
- *
- * @param array $table Table name
- * @param string|array $conds Array of conditions. See $conds in DatabaseBase::select()
- * for the format. Use $conds == "*" to delete all rows
- * @param string $fname Name of the calling function
- * @throws DBUnexpectedError
- * @return bool|ResultWrapper
- */
public function delete( $table, $conds, $fname = __METHOD__ ) {
if ( !$conds ) {
throw new DBUnexpectedError( $this, 'DatabaseBase::delete() called with no conditions' );
return $this->query( $sql, $fname );
}
- /**
- * INSERT SELECT wrapper. Takes data from a SELECT query and inserts it
- * into another table.
- *
- * @param string $destTable The table name to insert into
- * @param string|array $srcTable May be either a table name, or an array of table names
- * to include in a join.
- *
- * @param array $varMap Must be an associative array of the form
- * array( 'dest1' => 'source1', ...). Source items may be literals
- * rather than field names, but strings should be quoted with
- * DatabaseBase::addQuotes()
- *
- * @param array $conds Condition array. See $conds in DatabaseBase::select() for
- * the details of the format of condition arrays. May be "*" to copy the
- * whole table.
- *
- * @param string $fname The function name of the caller, from __METHOD__
- *
- * @param array $insertOptions Options for the INSERT part of the query, see
- * DatabaseBase::insert() for details.
- * @param array $selectOptions Options for the SELECT part of the query, see
- * DatabaseBase::select() for details.
- *
- * @return ResultWrapper
- */
public function insertSelect( $destTable, $srcTable, $varMap, $conds,
$fname = __METHOD__,
$insertOptions = array(), $selectOptions = array()
. "{$limit} ";
}
- /**
- * Returns true if current database backend supports ORDER BY or LIMIT for separate subqueries
- * within the UNION construct.
- * @return bool
- */
public function unionSupportsOrderAndLimit() {
return true; // True for almost every DB supported
}
- /**
- * Construct a UNION query
- * This is used for providing overload point for other DB abstractions
- * not compatible with the MySQL syntax.
- * @param array $sqls SQL statements to combine
- * @param bool $all Use UNION ALL
- * @return string SQL fragment
- */
public function unionQueries( $sqls, $all ) {
$glue = $all ? ') UNION ALL (' : ') UNION (';
return '(' . implode( $glue, $sqls ) . ')';
}
- /**
- * Returns an SQL expression for a simple conditional. This doesn't need
- * to be overridden unless CASE isn't supported in your DBMS.
- *
- * @param string|array $cond SQL expression which will result in a boolean value
- * @param string $trueVal SQL expression to return if true
- * @param string $falseVal SQL expression to return if false
- * @return string SQL fragment
- */
public function conditional( $cond, $trueVal, $falseVal ) {
if ( is_array( $cond ) ) {
$cond = $this->makeList( $cond, LIST_AND );
return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
}
- /**
- * Returns a comand for str_replace function in SQL query.
- * Uses REPLACE() in MySQL
- *
- * @param string $orig Column to modify
- * @param string $old Column to seek
- * @param string $new Column to replace with
- *
- * @return string
- */
public function strreplace( $orig, $old, $new ) {
return "REPLACE({$orig}, {$old}, {$new})";
}
- /**
- * Determines how long the server has been up
- * STUB
- *
- * @return int
- */
public function getServerUptime() {
return 0;
}
- /**
- * Determines if the last failure was due to a deadlock
- * STUB
- *
- * @return bool
- */
public function wasDeadlock() {
return false;
}
- /**
- * Determines if the last failure was due to a lock timeout
- * STUB
- *
- * @return bool
- */
public function wasLockTimeout() {
return false;
}
- /**
- * Determines if the last query error was something that should be dealt
- * with by pinging the connection and reissuing the query.
- * STUB
- *
- * @return bool
- */
public function wasErrorReissuable() {
return false;
}
- /**
- * Determines if the last failure was due to the database being read-only.
- * STUB
- *
- * @return bool
- */
public function wasReadOnlyError() {
return false;
}
* Returns whatever the callback function returned on its successful,
* iteration, or false on error, for example if the retry limit was
* reached.
- *
* @return mixed
- * @throws DBQueryError
+ * @throws DBUnexpectedError
+ * @throws Exception
*/
public function deadlockLoop() {
$args = func_get_args();
$this->begin( __METHOD__ );
$retVal = null;
+ /** @var Exception $e */
$e = null;
do {
try {
}
}
- /**
- * Wait for the slave to catch up to a given master position.
- *
- * @param DBMasterPos $pos
- * @param int $timeout The maximum number of seconds to wait for
- * synchronisation
- * @return int Zero if the slave was past that position already,
- * greater than zero if we waited for some period of time, less than
- * zero if we timed out.
- */
public function masterPosWait( DBMasterPos $pos, $timeout ) {
# Real waits are implemented in the subclass.
return 0;
}
- /**
- * Get the replication position of this slave
- *
- * @return DBMasterPos|bool False if this is not a slave.
- */
public function getSlavePos() {
# Stub
return false;
}
- /**
- * Get the position of this master
- *
- * @return DBMasterPos|bool False if this is not a master
- */
public function getMasterPos() {
# Stub
return false;
}
- /**
- * Run an anonymous function as soon as there is no transaction pending.
- * If there is a transaction and it is rolled back, then the callback is cancelled.
- * Queries in the function will run in AUTO-COMMIT mode unless there are begin() calls.
- * Callbacks must commit any transactions that they begin.
- *
- * This is useful for updates to different systems or when separate transactions are needed.
- * For example, one might want to enqueue jobs into a system outside the database, but only
- * after the database is updated so that the jobs will see the data when they actually run.
- * It can also be used for updates that easily cause deadlocks if locks are held too long.
- *
- * @param callable $callback
- * @since 1.20
- */
final public function onTransactionIdle( $callback ) {
$this->mTrxIdleCallbacks[] = array( $callback, wfGetCaller() );
if ( !$this->mTrxLevel ) {
}
}
- /**
- * Run an anonymous function before the current transaction commits or now if there is none.
- * If there is a transaction and it is rolled back, then the callback is cancelled.
- * Callbacks must not start nor commit any transactions.
- *
- * This is useful for updates that easily cause deadlocks if locks are held too long
- * but where atomicity is strongly desired for these updates and some related updates.
- *
- * @param callable $callback
- * @since 1.22
- */
final public function onTransactionPreCommitOrIdle( $callback ) {
if ( $this->mTrxLevel ) {
$this->mTrxPreCommitCallbacks[] = array( $callback, wfGetCaller() );
}
}
- /**
- * Begin an atomic section of statements
- *
- * If a transaction has been started already, just keep track of the given
- * section name to make sure the transaction is not committed pre-maturely.
- * This function can be used in layers (with sub-sections), so use a stack
- * to keep track of the different atomic sections. If there is no transaction,
- * start one implicitly.
- *
- * The goal of this function is to create an atomic section of SQL queries
- * without having to start a new transaction if it already exists.
- *
- * Atomic sections are more strict than transactions. With transactions,
- * attempting to begin a new transaction when one is already running results
- * in MediaWiki issuing a brief warning and doing an implicit commit. All
- * atomic levels *must* be explicitly closed using DatabaseBase::endAtomic(),
- * and any database transactions cannot be began or committed until all atomic
- * levels are closed. There is no such thing as implicitly opening or closing
- * an atomic section.
- *
- * @since 1.23
- * @param string $fname
- * @throws DBError
- */
final public function startAtomic( $fname = __METHOD__ ) {
if ( !$this->mTrxLevel ) {
$this->begin( $fname );
$this->mTrxAtomicLevels[] = $fname;
}
- /**
- * Ends an atomic section of SQL statements
- *
- * Ends the next section of atomic SQL statements and commits the transaction
- * if necessary.
- *
- * @since 1.23
- * @see DatabaseBase::startAtomic
- * @param string $fname
- * @throws DBError
- */
final public function endAtomic( $fname = __METHOD__ ) {
if ( !$this->mTrxLevel ) {
throw new DBUnexpectedError( $this, 'No atomic transaction is open.' );
$this->endAtomic( $fname );
}
- /**
- * Begin a transaction. If a transaction is already in progress,
- * that transaction will be committed before the new transaction is started.
- *
- * Note that when the DBO_TRX flag is set (which is usually the case for web
- * requests, but not for maintenance scripts), any previous database query
- * will have started a transaction automatically.
- *
- * Nesting of transactions is not supported. Attempts to nest transactions
- * will cause a warning, unless the current transaction was started
- * automatically because of the DBO_TRX flag.
- *
- * @param string $fname
- * @throws DBError
- */
final public function begin( $fname = __METHOD__ ) {
if ( $this->mTrxLevel ) { // implicit commit
if ( $this->mTrxAtomicLevels ) {
$this->mTrxLevel = 1;
}
- /**
- * Commits a transaction previously started using begin().
- * If no transaction is in progress, a warning is issued.
- *
- * Nesting of transactions is not supported.
- *
- * @param string $fname
- * @param string $flush Flush flag, set to 'flush' to disable warnings about
- * explicitly committing implicit transactions, or calling commit when no
- * transaction is in progress. This will silently break any ongoing
- * explicit transaction. Only set the flush flag if you are sure that it
- * is safe to ignore these warnings in your context.
- * @throws DBUnexpectedError
- */
final public function commit( $fname = __METHOD__, $flush = '' ) {
if ( $this->mTrxLevel && $this->mTrxAtomicLevels ) {
// There are still atomic sections open. This cannot be ignored
}
}
- /**
- * Rollback a transaction previously started using begin().
- * If no transaction is in progress, a warning is issued.
- *
- * No-op on non-transactional databases.
- *
- * @param string $fname
- * @param string $flush Flush flag, set to 'flush' to disable warnings about
- * calling rollback when no transaction is in progress. This will silently
- * break any ongoing explicit transaction. Only set the flush flag if you
- * are sure that it is safe to ignore these warnings in your context.
- * @throws DBUnexpectedError
- * @since 1.23 Added $flush parameter
- */
final public function rollback( $fname = __METHOD__, $flush = '' ) {
if ( $flush !== 'flush' ) {
if ( !$this->mTrxLevel ) {
'DatabaseBase::duplicateTableStructure is not implemented in descendant class' );
}
- /**
- * List all tables on the database
- *
- * @param string $prefix Only show tables with this prefix, e.g. mw_
- * @param string $fname Calling function name
- * @throws MWException
- * @return array
- */
function listTables( $prefix = null, $fname = __METHOD__ ) {
throw new MWException( 'DatabaseBase::listTables is not implemented in descendant class' );
}
throw new MWException( 'DatabaseBase::isView is not implemented in descendant class' );
}
- /**
- * Convert a timestamp in one of the formats accepted by wfTimestamp()
- * to the format used for inserting into timestamp fields in this DBMS.
- *
- * The result is unquoted, and needs to be passed through addQuotes()
- * before it can be included in raw SQL.
- *
- * @param string|int $ts
- *
- * @return string
- */
public function timestamp( $ts = 0 ) {
return wfTimestamp( TS_MW, $ts );
}
- /**
- * Convert a timestamp in one of the formats accepted by wfTimestamp()
- * to the format used for inserting into timestamp fields in this DBMS. If
- * NULL is input, it is passed through, allowing NULL values to be inserted
- * into timestamp fields.
- *
- * The result is unquoted, and needs to be passed through addQuotes()
- * before it can be included in raw SQL.
- *
- * @param string|int $ts
- *
- * @return string
- */
public function timestampOrNull( $ts = null ) {
if ( is_null( $ts ) ) {
return null;
}
}
- /**
- * Ping the server and try to reconnect if it there is no connection
- *
- * @return bool Success or failure
- */
public function ping() {
# Stub. Not essential to override.
return true;
return 0;
}
- /**
- * Return the maximum number of items allowed in a list, or 0 for unlimited.
- *
- * @return int
- */
function maxListLen() {
return 0;
}
- /**
- * Some DBMSs have a special format for inserting into blob fields, they
- * don't allow simple quoted strings to be inserted. To insert into such
- * a field, pass the data through this function before passing it to
- * DatabaseBase::insert().
- *
- * @param string $b
- * @return string
- */
public function encodeBlob( $b ) {
return $b;
}
- /**
- * Some DBMSs return a special placeholder object representing blob fields
- * in result objects. Pass the object through this function to return the
- * original string.
- *
- * @param string|Blob $b
- * @return string
- */
public function decodeBlob( $b ) {
if ( $b instanceof Blob ) {
$b = $b->fetch();
return $b;
}
- /**
- * Override database's default behavior. $options include:
- * 'connTimeout' : Set the connection timeout value in seconds.
- * May be useful for very long batch queries such as
- * full-wiki dumps, where a single query reads out over
- * hours or days.
- *
- * @param array $options
- * @return void
- */
public function setSessionOptions( array $options ) {
}
}
}
- /**
- * Set variables to be used in sourceFile/sourceStream, in preference to the
- * ones in $GLOBALS. If an array is set here, $GLOBALS will not be used at
- * all. If it's set to false, $GLOBALS will be used.
- *
- * @param bool|array $vars Mapping variable name to value.
- */
public function setSchemaVars( $vars ) {
$this->mSchemaVars = $vars;
}
return array();
}
- /**
- * Check to see if a named lock is available (non-blocking)
- *
- * @param string $lockName Name of lock to poll
- * @param string $method Name of method calling us
- * @return bool
- * @since 1.20
- */
public function lockIsFree( $lockName, $method ) {
return true;
}
- /**
- * Acquire a named lock
- *
- * Named locks are not related to transactions
- *
- * @param string $lockName Name of lock to aquire
- * @param string $method Name of method calling us
- * @param int $timeout
- * @return bool
- */
public function lock( $lockName, $method, $timeout = 5 ) {
return true;
}
- /**
- * Release a lock
- *
- * Named locks are not related to transactions
- *
- * @param string $lockName Name of lock to release
- * @param string $method Name of method calling us
- *
- * @return int Returns 1 if the lock was released, 0 if the lock was not established
- * by this thread (in which case the lock is not released), and NULL if the named
- * lock did not exist
- */
public function unlock( $lockName, $method ) {
return true;
}
- /**
- * Check to see if a named lock used by lock() use blocking queues
- *
- * @return bool
- * @since 1.26
- */
public function namedLocksEnqueue() {
return false;
}
return 'SearchEngineDummy';
}
- /**
- * Find out when 'infinity' is. Most DBMSes support this. This is a special
- * keyword for timestamps in PostgreSQL, and works with CHAR(14) as well
- * because "i" sorts after all numbers.
- *
- * @return string
- */
public function getInfinity() {
return 'infinity';
}
- /**
- * Encode an expiry time into the DBMS dependent format
- *
- * @param string $expiry Timestamp for expiry, or the 'infinity' string
- * @return string
- */
public function encodeExpiry( $expiry ) {
return ( $expiry == '' || $expiry == 'infinity' || $expiry == $this->getInfinity() )
? $this->getInfinity()
: $this->timestamp( $expiry );
}
- /**
- * Decode an expiry time into a DBMS independent format
- *
- * @param string $expiry DB timestamp field value for expiry
- * @param int $format TS_* constant, defaults to TS_MW
- * @return string
- */
public function decodeExpiry( $expiry, $format = TS_MW ) {
return ( $expiry == '' || $expiry == 'infinity' || $expiry == $this->getInfinity() )
? 'infinity'
: wfTimestamp( $format, $expiry );
}
- /**
- * Allow or deny "big selects" for this session only. This is done by setting
- * the sql_big_selects session variable.
- *
- * This is a MySQL-specific feature.
- *
- * @param bool|string $value True for allow, false for deny, or "default" to
- * restore the initial value
- */
public function setBigSelects( $value = true ) {
// no-op
}