Re: SQL spec/implementation question: UPDATE

Albe Laurenz skrev:
> Tom Lane wrote:
>>> I don't have handy a spec guide.  Does this mean that MySQL
>>> is indeed showing incorrect behavior?
>> I think this is really outside the spec.
> [...]
>> There is not anything I can see addressing whether an
>> "update" should or should not be considered to occur if a
>> target column happens to not change as a result of a
>> commanded update.
>
> Moreover, I can think of one argument why an UPDATE that
> does not change the value of the row should still occur:
> There may be an ON UPDATE trigger on the table that you
> expect to fire whether or not the UPDATE was "optimized
> away".

This case seems indeed to be "broken" in MySQL.

Nis