Re: [HACKERS] Hot Standby utility and administrator functions

[Simon Riggs <simon(at)2ndQuadrant(dot)com>]

On Tue, 2008-10-21 at 09:44 +0200, Zeugswetter Andreas OSB sIT wrote:
> > > * pg_last_recovered_xact_xid()
> > > Will throw an ERROR if *not* executed in recovery mode.
> > > returns bigint
> > >
> > > * pg_last_completed_xact_xid()
> > > Will throw an ERROR *if* executed in recovery mode.
> > > returns bigint
> >
> > Should these return xid?
> 
> And shouldn't these two be folded together ?
> It seems most usages of this xid(/lsn?) will be agnostic to the
> recovery mode. Or if not, it seems more convenient to have a function
> that returns both recovery mode and xid, no ?

You are right that it would be better to have a single function.
Functions that return multiple values are a pain to use and develop,
plus we can always run the other function if we are in doubt.

txid_last_completed() returns bigint (txid) seems better.

I am more than happy to add an id version as well, if anybody sees the
need for that. Just say.

-- 
 Simon Riggs           www.2ndQuadrant.com
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