Re: Non-reserved replication slots and slot advancing

On 2018-Jul-09, Andres Freund wrote:

> On 2018-07-09 15:48:33 +0900, Michael Paquier wrote:

> > +    if (XLogRecPtrIsInvalid(MyReplicationSlot->data.restart_lsn))
> > +    {
> > +        ReplicationSlotRelease();
> > +        ereport(ERROR,
> > +                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
> > +                 errmsg("cannot move slot not reserving WAL")));
> > +    }
> > +
> 
> I don't like this error message. It's unclear what refers to exactly
> what.  Nor is "move" a terminology used otherwise.  How about:
> "cannot advance replication slot that has not previously reserved WAL"
> or something similar?
> 
> Also, ERRCODE_FEATURE_NOT_SUPPORTED doesn't quite seem right. How about
> ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE?

+1 to both of Andres' suggestions.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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