Re: Error code for "terminating connection due to conflict with recovery"

Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
> On Mon, 2011-01-31 at 11:24 -0500, Robert Haas wrote:
>> , or to use a new
>> error code. ERRCODE_ADMIN_SHUTDOWN is just strange.

> It's not strange at all. It's the same error code as we use for all of
> the other cases listed. We need that because it is the current
> catch-all errcode for "cannot retry".

> The purpose of errcodes is to allow programs to check them and then act.
> It's pointless to add a new errcode that is so rare that nobody will
> ever program for it because they won't expect it, let alone test for it.
> Or at least won't assign any sensible priority to handling that error.

The trouble with ERRCODE_ADMIN_SHUTDOWN is that it might lead a
connection pooler to expect that *all* its connections are going bad,
not just the ones that are connected to a specific database. I think
this is a bad decision. Programs that are interested in testing for this
case at all are likely to need to be worried about that distinction.

Also, while I believe that ERRCODE_T_R_DEADLOCK_DETECTED is a reasonable
catchall retry code, I don't think it's equally sane to think that
ERRCODE_ADMIN_SHUTDOWN is a catchall non-retry code.

regards, tom lane