MySQL Forums
Forum List  »  Performance

Re: Limit for looping ANDs to a query
Posted by: Peter Zaitsev
Date: February 04, 2005 12:02PM


It does not make much sense in the form you have described it

field=Const1 and field=Const2 is always false if Const1!=Const2 :)

If you mean different fields there are a lot of questions to ask - are you going to index anything ? How large is the table, what is the chance of having clause matched

It should affect query parsing as well as CPU portion of execution at some extent -
if first clause is false MySQL will not evaluate second.

This is the case when having simple benchmark is easier and gives more accurate results than looking for theoretical answer :)

Options: ReplyQuote

Written By
February 01, 2005 04:12PM
Re: Limit for looping ANDs to a query
February 04, 2005 12:02PM

Sorry, you can't reply to this topic. It has been closed.

Content reproduced on this site is the property of the respective copyright holders. It is not reviewed in advance by Oracle and does not necessarily represent the opinion of Oracle or any other party.