Re: Effects of cascading references in foreign keys

Would someone please find the answer to Tom's last question?

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Tom Lane wrote:
> I wrote:
> > Looking at this, I wonder if there isn't a bug or at least an
> > inefficiency in 8.1.  The KeysEqual short circuit tests are still there
> > in ri_triggers.c; aren't they now redundant with the test in triggers.c?
> > And don't they need to account for the special case mentioned in the
> > comment in triggers.c, that the RI check must still be done if we are
> > looking at a row updated by the same transaction that created it?
>
> OK, I take back the possible-bug comment: the special case only applies
> to the FK-side triggers, which is to say RI_FKey_check, and that routine
> doesn't attempt to skip the check on equal old/new keys.  I'm still
> wondering though if the KeysEqual tests in the other RI triggers aren't
> now a waste of cycles.
>
>             regards, tom lane
>
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