Re: Append to a GUC parameter ?

Bruce Momjian wrote:
> On Tue, Aug  5, 2014 at 12:52:51PM -0700, Josh Berkus wrote:
> > On 08/05/2014 11:12 AM, Jerry Sievers wrote:
> > > shared_preload_libraries += auto_explain
> > > 
> > > Would do the trick.
> > > 
> > > I've  never heard this mentioned before so presume not many have
> > > contemplated this.
> > 
> > It's been discussed.
> > 
> > However, other than shared_preload_libraries, I can't think of a GUC
> > which would benefit from this.  Can you?
> 
> search_path?

Almost anything that's marked GUC_LIST_INPUT.  A quick grep shows some
variables for which it doesn't make sense, such as DateStyle, and others
for which it would, such as temp_tablespaces, synchronous_standby_names,
listen_addresses, and the various preload_libraries params.  Not sure
about log_destination.

I think this merits a new GUC flag, say GUC_LIST_ADDITIVE.

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