On Wed, Apr 18, 2007 at 07:51:48AM -0700, Stephan Szabo wrote: > On Tue, 17 Apr 2007, Tom Lane wrote: > > > A recent discussion led me to the idea that FK triggers are fired > > unnecessarily during an UPDATE if the foreign-key column(s) > > contain any NULLs, because ri_KeysEqual() treats two nulls as > > unequal, and therefore we conclude the row has changed when it has > > not. I claim that both ri_KeysEqual() and ri_OneKeyEqual() could > > consider two nulls to be equal. Furthermore it seems like > > ri_AllKeysUnequal() should do so too; the case can't arise at the > > moment because the sole caller already knows that one of the key > > sets contains no nulls, but if this weren't so, the optimization > > would be actively wrong if we concluded that two nulls were > > unequal. > > Do you have any suggestions for alternate names? Keeping them using > Equal seems to be dangerous since people would likely expect it to > act like normal equality (with nulls being different).
How about NotDistinct as in SQL's IS NOT DISTINCT FROM ? Cheers, D -- David Fetter <[EMAIL PROTECTED]> http://fetter.org/ phone: +1 415 235 3778 AIM: dfetter666 Skype: davidfetter Remember to vote! Consider donating to PostgreSQL: http://www.postgresql.org/about/donate ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
