Re: pg_last_xact_replay_timestamp meaning

On Fri, Mar 18, 2011 at 7:23 PM, Bruce Momjian <bruce@momjian.us> wrote:
> I just applied a doc patch for pg_last_xact_replay_timestamp, and the
> text now says:
>
>       <entry>Get timestamp of last transaction replayed during recovery.
>        This is the time at which the commit or abort WAL record for that
>        transaction was generated on the primary.
>        If no transactions have been replayed during recovery, this function
>        returns NULL.  Otherwise, if recovery is still in progress this will
>        increase monotonically.  If recovery has completed then this value will
>        remain static at the value of the last transaction applied during that
>        recovery.  When the server has been started normally without recovery
>        the function returns NULL.
>
> Is this really the last commit/abort record or the last WAL record?
> What should it be?  Is the name of this function correct?  Do we care
> only about commit/abort records? Why?

Commit and abort records have a timestamp.  Other WAL records don't.

--
Robert Haas
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