Re: Client application name

On Wed, Oct 21, 2009 at 12:27 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Dave Page <dpage(at)pgadmin(dot)org> writes:
>> BTW, any thoughts on Heikki's suggestions of hacking about the
>> 'options' value or retrying the connection vs. just doing a SET
>> post-connection in libpq? It's pretty certain that whatever I choose
>> you probably won't like :-p
>
> The post-connect SET still seems like the best choice to me.
> It's mildly annoying that that won't help for log_connections
> messages, but in the big scheme of things that's really not a
> killer problem.

Are we really thinking about interposing an additional server
round-trip on every connection for such a marginal feature (to
paraphrase yourself)? That doesn't seem like a good trade-off.

> The retry approach is not too bad from a user perspective: it would
> only actually happen during a server version mismatch, which isn't
> *that* common.  My recollection though is that there's no graceful way
> to implement a retry in libpq; you'd need a significant amount of new,
> ugly, special-purpose code, with the complexity rising very fast if
> there's more than one reason to retry.  If you can figure out a clean
> implementation this one would be okay with me, but I'm dubious that
> it's worth the work.
>
> That options hack was just an ugly hack, I don't like it at all ---
> mainly because I don't believe that approach scales to solve more
> than one case either.

Either way, seems like you can try it with all the options and the
back up one major release at a time until you find compatibility.
It's only O(features), not O(2^features).

...Robert