Re: MYSQL optimizer: Handling Subqueires
OK. But then isn't it true that the optimizer is meant to choose the access plan for a query to be executed? Now this is a compile time process and should not include any type of execution of any part of the query whatsoever. then why it is doing so?
So, if it is the case as you described wherein sub-queries are compiled-planned-executed and then outer query are compiled-planned, then can this be considered as an optimization process??
Because doesn't 13 hours time to explain a query distort the whole purpose of the query optimizer? Or is it that the query ran by you was big and computational-intensive enough so as to cause such explain time and it would have caused large response times when whole query is actually executed?
Kindly guide me through the issue.
Thanks.
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Re: MYSQL optimizer: Handling Subqueires
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