Re: Proposal for Allow postgresql.conf values to be changed via SQL - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Proposal for Allow postgresql.conf values to be changed via SQL
Date
Msg-id CA+Tgmob4Z_oVBOBENqJtG3U2C09Fj0PyhHb0fFX3XKWWtReMeQ@mail.gmail.com
Whole thread Raw
In response to Re: Proposal for Allow postgresql.conf values to be changed via SQL  (Amit kapila <amit.kapila@huawei.com>)
Responses Re: Proposal for Allow postgresql.conf values to be changed via SQL  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Wed, Nov 28, 2012 at 9:47 AM, Amit kapila <amit.kapila@huawei.com> wrote:
> 5. PERSISTENT Keyword is added to the reserved keyword list. As it was giving some errors given below while parsing
gram.y
>           15 shift/reduce conflicts .

Allow me to be the first to say that any syntax for this feature that
involves reserving new keywords is a bad syntax.

The cost of an unreserved keyword is that the parser gets a little
bigger and slows down, but previous experimentation shows that the
effect is pretty small.  However, adding a new reserved keyword breaks
user applications.  It is hardly difficult to imagine that there are a
decent number of users who have columns or PL/pgsql variables called
"persistent".  Let's not break them.  Instead, since there were
multiple proposed syntaxes for this feature, let's just pick one of
the other ones that doesn't have this problem.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



pgsql-hackers by date:

Previous
From: Robert Haas
Date:
Subject: Re: Hot Standby Feedback should default to on in 9.3+
Next
From: Tom Lane
Date:
Subject: Re: [PATCH] Patch to fix a crash of psql