Null should be renamed drunk. Treat nulls as drunks.... you may well speak to them but you never get any useful information back!
:-) Dave -----Original Message----- From: ProFox [mailto:[email protected]] On Behalf Of AndyHC Sent: 27 June 2013 11:53 To: [email protected] Subject: Re: [NF] Frustrating inconsistent SQL results As I've posted several times before - one day Null will bite your ass! On 27/06/2013 03:29, Ted Roche wrote: > NULL can be thought of the same as the value "I don't know." > > > select * from users where users in (select usernames from other table) > matches one to the other > > select * from users where users NOT IN (select usernames..) asks "Is > User Fred NOT IN a list that includes a value of I Don't Know?" --> > what's the answer? I DON'T KNOW. Fred might be in the list, and he > might not. Does Fred == NULL? I Don't Know. > > > > <snip> [excessive quoting removed by server] _______________________________________________ Post Messages to: [email protected] Subscription Maintenance: http://mail.leafe.com/mailman/listinfo/profox OT-free version of this list: http://mail.leafe.com/mailman/listinfo/profoxtech Searchable Archive: http://leafe.com/archives/search/profox This message: http://leafe.com/archives/byMID/profox/[email protected] ** All postings, unless explicitly stated otherwise, are the opinions of the author, and do not constitute legal or medical advice. This statement is added to the messages for those lawyers who are too stupid to see the obvious.
