Re: Proposal for Allow postgresql.conf values to be changed via SQL

On 12/03/2012 10:32 AM, Tom Lane wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Mon, Dec 3, 2012 at 6:38 AM, Amit Kapila <amit(dot)kapila(at)huawei(dot)com> wrote:
>>> opt_persistent: PERSISTENT { $$ = TRUE; }
>>> | /*EMPTY*/ %prec Op { $$ = FALSE; }
>>> ;
>>>
>>> I am not sure if there are any problems with above change.
>> We usually try to avoid operator precedence declarations. They
>> sometimes have unforeseen consequences.
> Yes. This is not an improvement over factoring out opt_persistent as
> I recommended previously.

This is by no means the first time this has come up. See
<http://wiki.postgresql.org/wiki/Fixing_shift/reduce_conflicts_in_Bison>

cheers

andrew