added SET to the list of write type queries
diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 5a55002..a5ca75d 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -576,7 +576,7 @@
 	 */	

 	function is_write_type($sql)

 	{

-		if (! preg_match('/^\s*"?(INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|LOAD DATA|COPY|ALTER|GRANT|REVOKE|LOCK|UNLOCK)\s+/i', $sql))

+		if (! preg_match('/^\s*"?(SET|INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|LOAD DATA|COPY|ALTER|GRANT|REVOKE|LOCK|UNLOCK)\s+/i', $sql))

 		{

 			return FALSE;

 		}