- Patch #22911 by Cvgbe: fixed table locking in PostgreSQL. You'll have to

use db_lock_table() and db_unlock_tables() for your code to be compatible.

includes/database.mysql.inc

@@ -269,6 +269,21 @@ function db_escape_string($text) {
   return addslashes($text);
 }
 
+/**
+ * Lock a table.
+ */
+function db_lock_table($table) {
+  db_query('LOCK TABLES {%s} WRITE', $table);
+}
+
+/**
+ * Unlock all locked tables.
+ */
+function db_unlock_tables() {
+  db_query('UNLOCK TABLES');
+}
+
+
 /**
  * @} End of "ingroup database".
  */

includes/database.pgsql.inc

@@ -255,6 +255,22 @@ function db_escape_string($text) {
   return pg_escape_string($text);
 }
 
+/**
+ * Lock a table.
+ * This function automatically starts a transaction.
+ */
+function db_lock_table($table) {
+  db_query('BEGIN; LOCK TABLE {%s} IN EXCLUSIVE MODE', $table);
+}
+
+/**
+ * Unlock all locked tables.
+ * This function automatically commits a transation.
+ */
+function db_unlock_tables() {
+  db_query('COMMIT');
+}
+
 /**
  * @} End of "ingroup database".
  */