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Re: Simple Query - but explain worries me
Posted by: Konstantin Osipov
Date: January 02, 2006 05:22PM

I wouldn't worry about that unless there is a clear evidence that the new plan is slower.
The optimizer performes a few 'dives' into the index to estimate the average number of records in range, and based on that, chooses the join order.
As long as the query is as fast as in 4.1 there is nothing to worry about.
Bear in mind that 5.0 adds new table access methods, such as index merge, and has other interesting optimizations that can influence the choice of the execution plan.
So, to sum up:
- it would be nice to see the explain output
- there is nothing to worry about as long as the query is executed quickly enough

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Re: Simple Query - but explain worries me
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