Re: Re: making write location work (was: Efficient transaction-controlled synchronous replication)

On Thu, Mar 24, 2011 at 2:28 PM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> The protocol supports sending two values, so two are displayed.
>
> If you wish to remove one from the display then that only makes sense
> if you also prevent the protocol from supporting two values.
>
> There is no benefit in doing that, so why do it? We are going to put
> that back in 9.2 if you remove it now. Why not leave it, so we don't
> need to rewrite all the monitoring tools that will use this view?

If we're going to put it back in 9.2, then we shouldn't remove it now.
We should just make it work. It's a three line patch. If 9.2 is
going to meaningfully distinguish between write location and flush
location, then we may as well do the same thing in 9.1. Then we'll be
ahead of the game: not only will the view have the same columns in
both releases, but they'll actually have the same semantics in both
releases.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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