>The select is the same as you're currently using. I just want to see how long will it take. Your actual select should use SUM and GROUP BY Client.ClientNo, but let's first find out without SUM.

I still do not understand. There is no direct relation with a record in my Client table.

IAC, here is the result:

Primary key SecondValue
4168140 14400
4168140 14400
4168140 10800