>>>> 2011/05/12 15:15 +0200, misiaq >>>> h...@tbbs.net wrote: (...) > > Is the optimizer so clever as to set that test outside the expression, and > only then evaluate it when "houmuch" and "SharePrice" are not equal? > >
Try it yourself: mysql > explain extended select * from table1; and then mysql > show warnings; You will see the optimized query. http://dev.mysql.com/doc/refman/5.0/en/explain.html <<<<<<<< Not much of an explanation of "EXPLAIN"--and this command is mostly about indexing and joining, in SQL of course of immens importance, and, to be sure, finding "houmuch" in my query costs JOINing and SUMming, but I see nothing relevant to my question. On the other hand, maybe finding "houmuch" costs so much more than the rest of the expression that it does not matter. In any case, there is here no answer to my question. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql?unsub=arch...@jab.org
