Re: Review: Fix snapshot taking inconsistencies

On Mon, Feb 28, 2011 at 1:22 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Marko Tiikkaja <marko(dot)tiikkaja(at)cs(dot)helsinki(dot)fi> writes:
>> [ latest version of snapshot-taking patch ]
>
> I started to look at this, and find myself fairly confused as to what
> the purpose is anymore.  Reviewing the thread, there has been a lot of
> discussion of refactoring the API of pg_parse_and_rewrite and related
> functions exported by postgres.c; but the current patch seems to have
> abandoned that goal (except for removing pg_parse_and_rewrite itself,
> which doesn't seem to me to have a lot of point except as part of a
> more general refactoring).  With respect to the issue of changing
> snapshot timing, most of the discussion around that seemed to start
> from assumptions about the behavior of wCTEs that we've now abandoned.
> And there was some discussion about rule behavior too, but it's not
> clear to me whether this patch intends to change that or not.  The
> lack of any documentation change doesn't help here.
>
> So: exactly what is the intended behavioral change as of now, and what
> is the argument supporting that change?

IIUC, this is the result of countless rounds of communal bikeshedding around:

http://archives.postgresql.org/pgsql-hackers/2010-07/msg01256.php

--
Robert Haas
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