Re: autocommit vs TRUNCATE et al - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: autocommit vs TRUNCATE et al
Date
Msg-id 200210212325.g9LNPP023448@candle.pha.pa.us
Whole thread Raw
In response to Re: autocommit vs TRUNCATE et al  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Tom Lane wrote:
> >> Perhaps RESET AUTOCOMMIT is a good enough answer?
> 
> > I was unclear on that.  RESET sets it back to the postgresql.conf value,
> > right?  Do we know that the session didn't change it earlier in the
> > script?  That's where it gets tricky.
> 
> You're postulating a scenario in which some snippet of code doesn't know
> what the surrounding script/application likes for AUTOCOMMIT, but does
> know enough about the context to know that it's not inside a transaction
> block already.  That combination seems moderately implausible to me.
> Anyone have an example where it'd really be useful?

Well, in most cases, if you don't know, you do BEGIN ... COMMIT, but in
the case of VACUUM/TRUNCATE, you can't do that, so you need some smarts.

It is a contrived example.  I am just throwing it out for illumination.
I often throw out scenarios at the edges to see if it strikes anyone as
a problem.  When it doesn't, we can move ahead.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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