AFAIK, (which isn't a vast amount...) the SELECT you're doing already *is* doing a join, but on the sql parser side internal to mysql.

Anytime you find yourself selecting something just so you can feed it back to the db as parameters, it's a good bet you're making perl do the work that should be done by the db. So, yes, you'd probably be much better off if you used a more complex DELETE statement.

--
"This alcoholism thing, I think it's just clever propaganda produced by people who want you to buy more bottled water." -- pedestrianwolf

In reply to Re: Slow script: DBI, MySQL, or just too much data? by naChoZ
in thread Slow script: DBI, MySQL, or just too much data? by menolly

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