Re: Largeobject Access Controls (r2460)

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Takahiro Itagaki <itagaki.takahiro@oss.ntt.co.jp>, KaiGai Kohei <kaigai@ak.jp.nec.com>, Jaime Casanova <jcasanov@systemguards.com.ec>, Greg Smith <greg@2ndquadrant.com>, pgsql-hackers@postgresql.org
Date: 2009-12-19T02:51:52Z
Lists: pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> Part of what I'm confused about (and what I think should be documented
> in a comment somewhere) is why we're using MVCC visibility in some
> places but not others.  In particular, there seem to be some bits of
> the comment that imply that we do this for read but not for write,
> which seems really strange.  It may or may not actually be strange,
> but I don't understand it.

It is supposed to depend on whether you opened the blob for read only
or for read write.  Please do not tell me that this patch broke that;
because if it did it broke pg_dump.

This behavior is documented at least here:
http://www.postgresql.org/docs/8.4/static/lo-interfaces.html#AEN36338

			regards, tom lane