Source
File: wp-includes/wp-db.php
protected function get_table_from_query( $query ) {
// Remove characters that can legally trail the table name.
$query = rtrim( $query, ';/-#' );
// Allow (select...) union [...] style queries. Use the first query's table name.
$query = ltrim( $query, "\r\n\t (" );
// Strip everything between parentheses except nested selects.
$query = preg_replace( '/\((?!\s*select)[^(]*?\)/is', '()', $query );
// Quickly match most common queries.
if ( preg_match(
'/^\s*(?:'
. 'SELECT.*?\s+FROM'
. '|INSERT(?:\s+LOW_PRIORITY|\s+DELAYED|\s+HIGH_PRIORITY)?(?:\s+IGNORE)?(?:\s+INTO)?'
. '|REPLACE(?:\s+LOW_PRIORITY|\s+DELAYED)?(?:\s+INTO)?'
. '|UPDATE(?:\s+LOW_PRIORITY)?(?:\s+IGNORE)?'
. '|DELETE(?:\s+LOW_PRIORITY|\s+QUICK|\s+IGNORE)*(?:.+?FROM)?'
. ')\s+((?:[0-9a-zA-Z$_.`-]|[\xC2-\xDF][\x80-\xBF])+)/is',
$query,
$maybe
) ) {
return str_replace( '`', '', $maybe[1] );
}
// SHOW TABLE STATUS and SHOW TABLES WHERE Name = 'wp_posts'
if ( preg_match( '/^\s*SHOW\s+(?:TABLE\s+STATUS|(?:FULL\s+)?TABLES).+WHERE\s+Name\s*=\s*("|\')((?:[0-9a-zA-Z$_.-]|[\xC2-\xDF][\x80-\xBF])+)\\1/is', $query, $maybe ) ) {
return $maybe[2];
}
/*
* SHOW TABLE STATUS LIKE and SHOW TABLES LIKE 'wp\_123\_%'
* This quoted LIKE operand seldom holds a full table name.
* It is usually a pattern for matching a prefix so we just
* strip the trailing % and unescape the _ to get 'wp_123_'
* which drop-ins can use for routing these SQL statements.
*/
if ( preg_match( '/^\s*SHOW\s+(?:TABLE\s+STATUS|(?:FULL\s+)?TABLES)\s+(?:WHERE\s+Name\s+)?LIKE\s*("|\')((?:[\\\\0-9a-zA-Z$_.-]|[\xC2-\xDF][\x80-\xBF])+)%?\\1/is', $query, $maybe ) ) {
return str_replace( '\\_', '_', $maybe[2] );
}
// Big pattern for the rest of the table-related queries.
if ( preg_match(
'/^\s*(?:'
. '(?:EXPLAIN\s+(?:EXTENDED\s+)?)?SELECT.*?\s+FROM'
. '|DESCRIBE|DESC|EXPLAIN|HANDLER'
. '|(?:LOCK|UNLOCK)\s+TABLE(?:S)?'
. '|(?:RENAME|OPTIMIZE|BACKUP|RESTORE|CHECK|CHECKSUM|ANALYZE|REPAIR).*\s+TABLE'
. '|TRUNCATE(?:\s+TABLE)?'
. '|CREATE(?:\s+TEMPORARY)?\s+TABLE(?:\s+IF\s+NOT\s+EXISTS)?'
. '|ALTER(?:\s+IGNORE)?\s+TABLE'
. '|DROP\s+TABLE(?:\s+IF\s+EXISTS)?'
. '|CREATE(?:\s+\w+)?\s+INDEX.*\s+ON'
. '|DROP\s+INDEX.*\s+ON'
. '|LOAD\s+DATA.*INFILE.*INTO\s+TABLE'
. '|(?:GRANT|REVOKE).*ON\s+TABLE'
. '|SHOW\s+(?:.*FROM|.*TABLE)'
. ')\s+\(*\s*((?:[0-9a-zA-Z$_.`-]|[\xC2-\xDF][\x80-\xBF])+)\s*\)*/is',
$query,
$maybe
) ) {
return str_replace( '`', '', $maybe[1] );
}
return false;
}