Use the following rules and guidelines when you configure the Integration Service to push a Lookup transformation with an SQL override to a database:
You cannot append an ORDER BY clause to the SQL statement in the lookup override. The session fails if you append an ORDER BY clause.
Verify that the SQL override selects all ports in the Lookup transformation, in the same order that the ports appear in the Lookup transformation.
The session fails if the SELECT statement in the SQL override refers to a database sequence.
The Integration Service processes a Lookup transformation with an SQL override if the transformation contains Informatica outer join syntax in the SQL override. Use ANSI outer join syntax in the SQL override to push the transformation to a database.