Re: ON COMMIT temp table handling

Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> Tom Lane wrote:
>> Why is temp table handling in need of looking into xact.c's private
>> state? There is no other AtEOXact routine anywhere that does this.
>> ISTM either the above code is wrong, or every other AtEOXact routine
>> is wrong.

> I looked at that. The basic issue is that Gavin wants special handling
> for ON COMMIT, meaning he only wants to activate the ON COMMIT code when
> the transaction is committed and it is an end block, or it is not a
> commit but it is an abort.

I eventually realized that the problem is that his AtEOXact routine
needs to be split in two pieces. The actual ON COMMIT DROP or DELETE
ROWS action has to happen *before* we record transaction commit.
(Imagine what happens if we get an error while doing that part.)
But the cleanup of the list of on-commit objects should happen
afterwards. I think if you look at the version I committed this
afternoon, you'll be much happier.

> I have to say I am confused by the various
> TBLOCK values and their progression. I can't find any comments on them
> and the code seems contorted.

I think xact.c has more generality than it actually needs --- some of
the TBLOCK states could probably be eliminated. I'm not really excited
about rewriting it though; it works and has worked for years.

regards, tom lane