Re: COPY with no WAL, in certain circumstances - Mailing list pgsql-patches

From Tom Lane
Subject Re: COPY with no WAL, in certain circumstances
Date
Msg-id 2036.1168136282@sss.pgh.pa.us
Whole thread Raw
In response to Re: COPY with no WAL, in certain circumstances  ("Simon Riggs" <simon@2ndquadrant.com>)
Responses Re: COPY with no WAL, in certain circumstances  ("Simon Riggs" <simon@2ndquadrant.com>)
List pgsql-patches
"Simon Riggs" <simon@2ndquadrant.com> writes:
> The rule is: if the relfilenode for a table is new in this transaction
> (and therefore the whole things will be dropped at end-of-transaction)
> then *all* COPY commands are able to avoid writing WAL safely, if:
> - PITR is not enabled
> - there is no active portal (which could have been opened on an earlier
> commandid and could therefore see data prior to the switch to the new
> relfilenode). In those cases, *not* using WAL causes no problems at all,
> so sleep well without it.

Uh ... what in the world has an active portal got to do with it?
I think you've confused snapshot considerations with crash recovery.

            regards, tom lane

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