That would be normal for most programming languages, but I can't find that spelled out anywhere in the MySQL documentation. However the comments at the bottom of this page:
http://dev.mysql.com/doc/refman/5.1/en/where-optimizations.html are interesting. -- Walt On 12/23/2011 04:48 PM, Wade Preston Shearer wrote: > Am I correct in my understanding that the right side of an OR statement in an > MySQL query doesn't get evaluated unless the left side fails? I have a query > where the left-side case of an OR occurs often and produces an efficient > query and the right-side happens only occasionally and produces a slower, > less efficient query. If the query always checks both but only uses the left > if it is true, then I'd be better served to move it into two queries. If it > only checks the right-side condition if the left-side fails though, then > keeping it in one makes sense. > > _______________________________________________ > > UPHPU mailing list > [email protected] > http://uphpu.org/mailman/listinfo/uphpu > IRC: #uphpu on irc.freenode.net _______________________________________________ UPHPU mailing list [email protected] http://uphpu.org/mailman/listinfo/uphpu IRC: #uphpu on irc.freenode.net
