Issue #1868972 by jweowu, DanChadwick: Db_query_temporary() fails to create a table when the SQL has leading whitespace.

CHANGELOG.txt

@@ -1,6 +1,10 @@
 
 Drupal 7.28, xxxx-xx-xx (development version)
 -----------------------
+- Changed the behavior of db_query_temporary() so that it works on SELECT
+  queries even when they have leading comments/whitespace. A side effect of
+  this fix is that db_query_temporary() will now fail with an error if it is
+  ever used on non-SELECT queries.
 - Added a "node_admin_filter" tag to the database query used to build the list
   of nodes on the content administration page, to make it easier to alter.
 - Made the cron queue system log any exceptions that are thrown while an item

includes/database/mysql/database.inc

@@ -90,7 +90,7 @@ class DatabaseConnection_mysql extends DatabaseConnection {
 
   public function queryTemporary($query, array $args = array(), array $options = array()) {
     $tablename = $this->generateTemporaryTableName();
-    $this->query(preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE {' . $tablename . '} Engine=MEMORY SELECT', $query), $args, $options);
+    $this->query('CREATE TEMPORARY TABLE {' . $tablename . '} Engine=MEMORY ' . $query, $args, $options);
     return $tablename;
   }
 

includes/database/pgsql/database.inc

@@ -146,7 +146,7 @@ class DatabaseConnection_pgsql extends DatabaseConnection {
 
   public function queryTemporary($query, array $args = array(), array $options = array()) {
     $tablename = $this->generateTemporaryTableName();
-    $this->query(preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE {' . $tablename . '} AS SELECT', $query), $args, $options);
+    $this->query('CREATE TEMPORARY TABLE {' . $tablename . '} AS ' . $query, $args, $options);
     return $tablename;
   }
 

includes/database/sqlite/database.inc

@@ -250,7 +250,7 @@ class DatabaseConnection_sqlite extends DatabaseConnection {
     $prefixes[$tablename] = '';
     $this->setPrefix($prefixes);
 
-    $this->query(preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE ' . $tablename . ' AS SELECT', $query), $args, $options);
+    $this->query('CREATE TEMPORARY TABLE ' . $tablename . ' AS ' . $query, $args, $options);
     return $tablename;
   }
 

modules/simpletest/tests/database_test.test

@@ -3137,6 +3137,15 @@ class DatabaseTemporaryQueryTestCase extends DrupalWebTestCase {
 
     $this->assertEqual($this->countTableRows($table_name_system), $this->countTableRows("system"), 'A temporary table was created successfully in this request.');
     $this->assertEqual($this->countTableRows($table_name_users), $this->countTableRows("users"), 'A second temporary table was created successfully in this request.');
+
+    // Check that leading whitespace and comments do not cause problems
+    // in the modified query.
+    $sql = "
+      -- Let's select some rows into a temporary table
+      SELECT name FROM {test}
+    ";
+    $table_name_test = db_query_temporary($sql, array());
+    $this->assertEqual($this->countTableRows($table_name_test), $this->countTableRows('test'), 'Leading white space and comments do not interfere with temporary table creation.');
   }
 }