Quote:
Originally Posted by helenp
I read that mysql will only use one index per table,...
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Not true. *PER* join, probably true. Maybe even per condition in the WHERE clause. But if you have multiple WHERE conditions, it can take advantage of multiple indexes. (It may not choose to. But that's a different thing. If a single index reduces the number of candidate records down to just a few, it's faster to then scan the records then invoke another index.)