How long does it take? Obviously you would want to run SELECT COUNT(*) instead of DELETE. That will tell you how long it will take and how many records will be deleted. You can also slap EXPLAIN in front to see how MySQL will go about executing the query.
On Wednesday, February 5, 2003, at 10:27 AM, Andy Smith wrote:
I wish to delete every row from data which is NOT referenced in tables t1 and t2. The manual seems to suggest doing a three table left join and matching on both t1.data_id and t2.data_id being NULL. I am concerned this would take way too long, though I can get away with only doing this query say once a week.
-- Brent Baisley Systems Architect Landover Associates, Inc. Search & Advisory Services for Advanced Technology Environments p: 212.759.6400/800.759.0577
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