Re: [ADMIN] 9.5 new setting "cluster name" and logging

On Tue, Feb 9, 2016 at 5:30 AM, Joe Conway <mail(at)joeconway(dot)com> wrote:
> On 02/08/2016 06:24 AM, Andres Freund wrote:
>> On 2016-01-29 22:19:45 -0800, Evan Rempel wrote:
>>> Now that there is a setting to give a cluster a "name", it would be nice to
>>> have an escape sequence in the log_line_prefix setting that could reference
>>> the cluster_name.
>>
>> I've argued[1][2] for this when cluster_name was introduced, but back
>> then I seemed to have been the only one arguing for it. Josh later
>> jumped that train.
>>
>> Given that we now had a number of people wishing for this, can we maybe
>> reconsider?
>
> Seems like a reasonable idea to me. But if we add a log_line_prefix
> setting, shouldn't we also add it to csvlog output too?

Here's a tiny patch adding support for %C to log_line_prefix (this was
part of the cluster_name patch that didn't go it).

Given that csvlog's output format is hardcoded in write_csvlog, how is
it supposed to evolve without upsetting consumers of this data?
Wouldn't we first need to add a GUC that lets you control the columns
it outputs?

--
Thomas Munro
http://www.enterprisedb.com