Changeset 39275 for trunk/src/wp-includes/wp-db.php

Timestamp:

11/17/2016 04:20:22 AM (4 years ago)

Author:

pento

Message:

Database: Add support for LIKE-escaped tables in ::get_table_from_query().

The SHOW TABLES LIKE query can be used to search for tables that match a pattern, wp\_123\_%, for example. While this isn't the name of an actual table, the wp_123_ prefix can be used by database drop-ins to direct the query correctly. This change removes the escaping and % modifier, to provide this usable prefix.

Props andy, pento.
Fixes #38751.

File:

• trunk/src/wp-includes/wp-db.php (modified) (1 diff)

trunk/src/wp-includes/wp-db.php

@@ -3038 +3038 @@
         }
 
-        // SHOW TABLE STATUS and SHOW TABLES
-        if ( preg_match( '/^\s*(?:'
-                . 'SHOW\s+TABLE\s+STATUS.+(?:LIKE\s+|WHERE\s+Name\s*=\s*)'
-                . '|SHOW\s+(?:FULL\s+)?TABLES.+(?:LIKE\s+|WHERE\s+Name\s*=\s*)'
-                . ')\W((?:[0-9a-zA-Z$_.`-]|[\xC2-\xDF][\x80-\xBF])+)\W/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] );
         }