Re: Trigger once again

On Thu, 2002-11-28 at 21:55, Adrian Klaver wrote:
> I have created the following function:
...
> IF new.tag_number=old.tag_number THEN
> RAISE EXCEPTION ''Number is already present '';
...
> The trigger seems to work to well. If I update values other than the
> tag_number I get the 'Number is already present' message. I am somewhat
> confused as their is no new.tag_number value being passed to the function.
> Can anyone set me straight?

NEW contains the whole changed record; OLD contains the record before
the change. If you "update values other than the tag_number", the
tag_number is not changed, therefore the condition is true.

--
Oliver Elphick Oliver(dot)Elphick(at)lfix(dot)co(dot)uk
Isle of Wight, UK http://www.lfix.co.uk/oliver
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"The earth is the LORD'S, and the fullness thereof; the
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