On Oct 22, 2007, at 11:01 AM, Alan Hodgson wrote:
On Sunday 21 October 2007, Kevin Hunter <hunteke@xxxxxxxxxxx> wrote:
Heh. And as Tom points out downthread, that "shortcut" probably
doesn't
gain anything in the long run.
Considering how expensive updates are in PostgreSQL, I suspect that
isn't
true.
No, the idea is that the vast majority of updates aren't going to
have this happen so you're waisting cpu cycles trying to determine
beforehand if the update will have any effect. The gain from not
running updates that actually wouldn't change any table data would be
dwarfed by the overhead of making that check on every update.
However, the current behaviour does seem to be logical; we did in
fact ask
for the row to be updated ...
Right. And, as someone else pointed out, it also allows any triggers
on the table to still run.
Erik Jones
Software Developer | Emma®
erik@xxxxxxxxxx
800.595.4401 or 615.292.5888
615.292.0777 (fax)
Emma helps organizations everywhere communicate & market in style.
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