Duplicate of: Should I use != or <> for not equal in TSQL
Within SQL Server's T-SQL should I use "<>" or "!=", or does it really even matter?
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Duplicate - http://stackoverflow.com/questions/723195/should-i-use-or-for-not-equal-in-tsql/723203#723203 – madcolor Apr 09 '09 at 13:42
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I don't know SQLServer, but the SQL standard uses '<>', so follow the standard
chburd
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1Woah woah woah, which is the T-SQL standard? I always thought != was the T-SQL, and <> being the MS-way? – Kieran Senior Apr 09 '09 at 13:41
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1T-SQL is short for Transact-SQL, which is Microsoft's SQL Server implementation of SQL. T-SQL supports ANSI SQL and more. – Adam Robinson Apr 09 '09 at 13:51
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I believe that != is T-SQL specific (i.e. not standard SQL). So, you should use <> if there's any chance that you'll ever port your code to use a different DBMS.
Personally, I would use <> and forget about it.
Ferruccio
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Typical SQL usage in my experience is to use <>. I've never seen anyone use !=; I wasn't even aware that worked.
Adam Robinson
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!= isn't part of the standard, but it is part of T-SQL..
Duplicate Post..
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these should go in the comments on the question so they're easier to see – nickf Apr 09 '09 at 13:41
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Fair point, technically an exact duplicate as the answer would be the same. – Kieran Senior Apr 09 '09 at 13:43
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Use <> since most people are familiar with that, and whenever NULLs are possible, remember that NULL is not equal to NULL, so this is sometimes necessary:
ISNULL(MY_FIELD,0) <> ISNULL(MY_FIELD,0)
JosephStyons
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2That would also equate a legit 0 to NULL, which may not be what you want. I always use (MY_FIELD1 <> MY_FIELD2 OR (MY_FIELD1 IS NULL AND MY_FIELD2 IS NULL)) but I'd be interested in seeing if someone else has a better way. – Misko Apr 09 '09 at 14:11
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Yes, that's a great point. The method you describe is more reliable. – JosephStyons Apr 09 '09 at 14:28
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I'd say it comes down to your coding conventions. I personally like to use != as <> reminds me of dirty dirty VB and gives me a bad gut feeling. Plus I comprehend it better as it is exact to C#'s not equal operator.
Pat
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