Place your (
SELECT a, b FROM KEY_TABLE kt JOIN......
UNION
SELECT a, b FROM KEY_TABLE kt JOIN......
UNION
SELECT a, b FROM KEY_TABLE kt JOIN......
) T0
code in temp table and add appropraite indexes (acc to outer query ) to it
then use that temp table in main query
PLUS
POST exec plan here (as OPC suggested above)
-------Bhuvnesh----------
I work only to learn Sql Server...though my company pays me for getting their stuff done;-)