[ci skip] Fix #861 (regression)
diff --git a/system/database/drivers/mssql/mssql_forge.php b/system/database/drivers/mssql/mssql_forge.php
index 24d1fc2..91b5794 100644
--- a/system/database/drivers/mssql/mssql_forge.php
+++ b/system/database/drivers/mssql/mssql_forge.php
@@ -113,6 +113,11 @@
 	 */
 	protected function _attr_type(&$attributes)
 	{
+		if (isset($attributes['CONSTRAINT']) && strpos($attributes['TYPE'], 'INT') !== FALSE)
+		{
+			unset($attributes['CONSTRAINT']);
+		}
+
 		switch (strtoupper($attributes['TYPE']))
 		{
 			case 'MEDIUMINT':