• ronmoses (1/16/2013)

    I just encountered this scenario this past week. The ISDATE() and ISNUMERIC() functions are practically useless when determining whether a string will safely convert to a datetime or numeric value, respectively. (For example, '$' passes ISNUMERIC().) So I figured why not put a TRY...CATCH in a function, try to convert the value, return 0 if it fails and 1 if it doesn't. Bingo, working ISDATE(). But no... denied. Oh well.


    Trust me, Ron - if it would have worked, you would have been appalled at the (lack of) performance.

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  • Hugo Kornelis (1/16/2013)

    Trust me, Ron - if it would have worked, you would have been appalled at the (lack of) performance.

    Oh, for sure. I would never have used it on a large number of records, or implemented it in production. This was a special case involving about 500 records, one of which was throwing a conversion error. Seemed like a better option than combing through them.

    Yes, it could have been scripted SP-style, but these were records being returned by a rather complex query someone else wrote; I was merely trying to help with the error. So I didn't have ready access to the underlying records, or else I would have gone that way.


    a haiku...

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    NULL is the unknown

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  • Interesting.

    I can't believe I've never tried to put a TRY/CATCH in a function before.

  • Nice question, did a little research on this to get it right, though I did do a double-read-and-analyze.


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  • Thanks for the question

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  • Good question. Had to read it twice to understand, so again it was knowing something and being careful to read it closely.




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  • Thanks for this good question. Recently I realized this when i try to use TRY CATCH to validate an insert operation inside a table function.

  • An easy and straightforward one - thanks!

  • I admit I didn't know this. Thanks for the knowledge.

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  • I never tried using TRY ..CATCH in a function. But today i learnt we can't use it.

    Desire to learn new things..

  • Easy One

  • Nice straightforward question.

    I find it a little irritating that try...catch is banned in multi-statement functions; I like to have clean eror management as much as possible, and cases where it isn't possible tend to irritate me. I guess it's a performance trade-off, though.


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