Re: WAL logging of SELECT ... INTO command - Mailing list pgsql-performance

From Tom Lane
Subject Re: WAL logging of SELECT ... INTO command
Date
Msg-id 16692.1143041726@sss.pgh.pa.us
Whole thread Raw
In response to Re: WAL logging of SELECT ... INTO command  ("Jim C. Nasby" <jnasby@pervasive.com>)
Responses Re: WAL logging of SELECT ... INTO command  (Csaba Nagy <nagy@ecircle-ag.com>)
List pgsql-performance
"Jim C. Nasby" <jnasby@pervasive.com> writes:
> Oh, so in other words, SELECT * INTO temp FROM table is inherently
> non-deterministic at the physical level, so the only way to be able to
> allow PITR to work is to duplicate all the physical changes. Darn.

Well, lemme put it this way: I'm not prepared to require that PG be
deterministic at the physical level.  One obvious source of
non-determinancy is the FSM, which is likely to hand out different free
space to different transactions depending on what else is going on at
the same time.  There are others, such as deliberately random
tie-breaking during btree index insertion.

            regards, tom lane

pgsql-performance by date:

Previous
From: "Jim C. Nasby"
Date:
Subject: Re: WAL logging of SELECT ... INTO command
Next
From: ashah
Date:
Subject: Massive Inserts Strategies