diff --git a/sql/engines/oracle.py b/sql/engines/oracle.py
index 4efb7820a1..6f25bbe71b 100644
--- a/sql/engines/oracle.py
+++ b/sql/engines/oracle.py
@@ -28,8 +28,9 @@ class OracleEngine(EngineBase):
 
     def __init__(self, instance=None):
         super(OracleEngine, self).__init__(instance=instance)
-        self.service_name = instance.service_name
-        self.sid = instance.sid
+        if instance:
+            self.service_name = instance.service_name
+            self.sid = instance.sid
 
     def get_connection(self, db_name=None):
         if self.conn: