Comments on: SQL CASE statement with NULLs

By: Patel Pinakin

Patel Pinakin — Sat, 03 Apr 2010 07:08:22 +0000

was just forgot the syntax,
thanx
u helped me recall…

keep posting…

By: Nayha

Nayha — Tue, 15 Sep 2009 11:18:18 +0000

very helpful. Thanks.

By: Mmark

Mmark — Thu, 19 Feb 2009 02:39:49 +0000

One more thnak you. It was a big helping.

By: Jason

Jason — Tue, 09 Dec 2008 17:46:27 +0000

Very useful to me as well. I’m glad that I was able to stumble upon this.

By: Sanjay

Sanjay — Wed, 08 Oct 2008 09:04:11 +0000

Good piece of information…..I had a confusion in writing a CASE statement with NULLS and this article solved that, Thanks

By: Ciro Theodoro

Ciro Theodoro — Fri, 15 Aug 2008 14:48:11 +0000

Very usefull. I was facing the same problem when I found this article. Thanks for that

By: Dan G. Switzer, II

Dan G. Switzer, II — Thu, 05 Jun 2008 13:50:53 +0000

The reason the first example doesn’t work is because NULL is never equal (=) to another value–even NULL = NULL will return false.

So you in your first example/attempt the code is essentially saying “WHERE price = NULL”, which will always fail. The reason the second example works is because you’re now using the correct expression for testing to see if a value is NULL–which is using the IS operator.

Obviously COALESCE works because if the value *is* NULL, it’s changing the value to 0.