Greg Stark wrote on 2004-09-27 08:17:Stephan Szabo <[EMAIL PROTECTED]> writes:Even simpler: COALESCE( a = b, a IS NULL AND b IS NULL )
>> On Sun, 26 Sep 2004 20:16:52 +0200, David Helgason <[EMAIL PROTECTED]> wrote:
>>> On a similar note, I've found myself wanting an extended '=' operator
>>> meaning
>>> (a = b or (a is null and b is null))
>
> The original does appear to be equivalent to "not(a is distinct from b)",
> although I'm not sure that's necessarily easier to use than the above.
I often do things like "coalesce(a,0) = coalesce(b,0)". (Or whatever value you know won't appear)
I'm not quite sure what is being accomplished here... My original expression wasn't that bad, just clunky. I'd prefer a === b or (a samevalue b), but the above just complicates matters. Also, a 'set' command outside the expression goes completely against the idea, that certain fields have 'null' as a legal, comparable value, while others do not.
Anyway, idle speculation :)
d.
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