Re: Comment in outfunc.c

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Tatsuo Ishii <ishii(at)postgresql(dot)org>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: Comment in outfunc.c
Date: 2014-10-25 01:28:25
Message-ID: 15666.1414200505@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Tatsuo Ishii <ishii(at)postgresql(dot)org> writes:
> I saw this comment in _outQuery() in outfuncs.c:

> WRITE_ENUM_FIELD(commandType, CmdType);
> WRITE_ENUM_FIELD(querySource, QuerySource);
> /* we intentionally do not print the queryId field */
> WRITE_BOOL_FIELD(canSetTag);

> What is the resoning behind the comment?

We don't want the queryId copied when a view/rule is reloaded,
since there's no guarantee that the algorithm for computing it
is stable for the life of a PG major version. Instead it's reset
to zero on reload, and any plugins that care can recompute it.

I suppose we could print it anyway and then ignore it on reload
but what's the point of that?

regards, tom lane

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Drew Crawford 2014-10-25 02:05:19 security barrier INSERT
Previous Message Tatsuo Ishii 2014-10-25 01:02:28 Comment in outfunc.c