Home Forums Article Discussions Article Discussions by Author Discuss content posted by Britt Cluff IsNumeric with NULL and Empty String RE: IsNumeric with NULL and Empty String

  • August 4, 2011 at 7:42 am

    #1363647

    Tom.Thomson (8/4/2011)

    I've always found it a bit disappointing that IsNumeric(Null) doesn't return NULL; after all, a NULL value doesn't contain any non-numeric characters, so it's not not numeric; and it doesn't contain any characters that are numeric, so it's not numeric either; so it should surely return NULL; just yet another case where (T-)SQL gets it wrong with NULL. But then IsNumeric is such an awful function anyway that that's teh least of its worries (perhaps the biggest is its name).

    Thanks for that - I've learned something new today!

    I always thought that the justification for things like '+' or '$' returning 1 for isNumeric was that it was possible to assign them to at least one numeric datatype, in this case money. But on that basis, shouldn't IsNumeric(NULL) also return 1, since NULL can be assigned to any numeric datatype? I'd have guessed at it returning NULL, but to return 0 is just bizarre.