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From:Michael Widenius Date:June 28 1999 10:27pm
Subject:EXPLAIN UPDATE
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>>>>> "Sasha" == Sasha Pachev <sasha@stripped> writes:

Sasha> As far as I know, EXPLAIN UPDATE is not supported in MySQL. The question
Sasha> is whether it is correct to assume that the same keys will be used for
Sasha> an update as for the equivalent select: SELECT * from table_to_update
Sasha> WHERE $update_constraint ?

Yes!

In most cases they should give the same explanation.
(The SELECT code has many optimisations stages that is not done on
UPDATE, because UPDATE only uses one table.  In some very rare cases this
may change how SELECT is done)

Regards,
Monty
Thread
EXPLAIN UPDATESasha Pachev21 Jun
  • EXPLAIN UPDATEMichael Widenius29 Jun