SQL GROUP BY and HAVING clauses can help summarize and filter data significantly faster than running multiple queries in a while loop.

Also - LanX's suggestion of having appropriate INDEXes should improve performance.

SQL help would be off-topic for this forum, so I'm resisting requesting schema information, and a better problem description.

                As a computer, I find your faith in technology amusing.

In reply to Re: Alternative for multiple while loops to improve performance by NetWallah
in thread Alternative for multiple while loops to improve performance by MissPerl

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