How many rows in the table, and how much does the serial column filter? If the filter on the 'serial' column filters a significant percentage, you might get good results from an index on that column, and maybe changing the filter to mastertable.serial in ('FF', 'CC', 'OO', 'NN' ). Then again, maybe not, because some databases would just convert the 'in' clause to joined 'or' clauses like you have anyway. Getting a query plan would help (do you know how to get one for your database?).

Also (unrelated), use RaiseError. You are checking the connect and execute, but not the fetch.

In reply to Re: DB Question, speed is the answer! by runrig
in thread DB Question, speed is the answer! by Anonymous Monk

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