In some cases, NOT IN is better than NOT EXISTS. In other cases, the opposite is true.
Moral: It never pays to discount an option out of hand - eg, NOT IN often works very very nicely for uncorrelated subqueries hth connor --- "Post, Ethan" <[EMAIL PROTECTED]> wrote: > Hold the press. NOT IN better than NOT EXISTS? Is > this theory or fact? If > so is there any supporting evidence out there? This > is the first I have > heard of this. > > Thanks! > > -----Original Message----- > Sent: Friday, November 15, 2002 11:35 AM > To: Multiple recipients of list ORACLE-L > > > Jerry, > > I suspect that the improvments are more likely due > to your > rewriting the WHERE clause rather than the use of > NOT EXISTS. > > Especially if the database were 9i, where NOT IN > actually > seems get a better execution path than NOT EXISTS. > > That original WHERE clause is really a piece of > work. > > Jared > > > > -- > Please see the official ORACLE-L FAQ: > http://www.orafaq.com > -- > Author: Post, Ethan > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 > http://www.fatcity.com > San Diego, California -- Mailing list and web > hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an > E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of > 'ListGuru') and in > the message BODY, include a line containing: UNSUB > ORACLE-L > (or the name of mailing list you want to be removed > from). You may > also send the HELP command for other information > (like subscribing). ===== Connor McDonald http://www.oracledba.co.uk http://www.oaktable.net "GIVE a man a fish and he will eat for a day. But TEACH him how to fish, and...he will sit in a boat and drink beer all day" __________________________________________________ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: =?iso-8859-1?q?Connor=20McDonald?= INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
