Re: [HACKERS] merging duplicate definitions of adjust_relid_set - Mailing list pgsql-hackers

From Robert Haas
Subject Re: [HACKERS] merging duplicate definitions of adjust_relid_set
Date
Msg-id CA+TgmobB9Vd4f9PXzND=4Az3DkYExOn4i-J8BESAPP9SnhTZQA@mail.gmail.com
Whole thread Raw
In response to Re: [HACKERS] merging duplicate definitions of adjust_relid_set  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Fri, Mar 17, 2017 at 1:50 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> While reviewing Ashutosh Bapat's partitionwise join code, I noticed
>> he'd run up against the problem that adjust_relid_set() is defined as
>> static in two different source files, and he wanted to call it from a
>> third file.  I didn't much like his solution to that problem, which
>> was to rename one of them and make that definition non-static; I think
>> it would be better to keep the existing name and stop defining it in
>> multiple places.  However, I discovered that there wasn't really an
>> obviously-good place to put the function; neither prepunion.c nor
>> rewriteManip.c, the two files that contain static versions as of now,
>> seem like an appropriate place from which to expose it, and I didn't
>> find anything else that I was wildly in love with, either.  The
>> attached patch puts it in var.c, because it didn't look horrible and I
>> thought it wasn't worth creating a new file just for this.
>
>> Objections, better ideas?
>
> I think it might be better to define it as a fundamental Bitmapset
> operation in nodes/bitmapset.c, along the lines of
>
> Bitmapset *bms_replace_member(const Bitmapset *bms, int member, int repl);
>
> This API would probably require giving up the property of not copying the
> set unless it changes, but I doubt that that's performance critical.

I thought of that, but I wasn't sure it was good in terms of clarity
to replace a function that works in terms of Relids with one that
works in terms of Bitmapset *.  I know they're the same, so it's just
a style thing.

But actually, I think my email was premature.  Actually, his patch
series first changes adjust_relid_set to take different arguments so
that it can do multiple translations at once, and then a later patch
in the series renames it.  So there's actually no need to merge the
definitions, because one of them ends up going away anyway.  So, uh,
never mind.

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



pgsql-hackers by date:

Previous
From: Corey Huinker
Date:
Subject: Re: [HACKERS] \if, \elseif, \else, \endif (was Re: PSQL commands:\quit_if, \quit_unless)
Next
From: Robert Haas
Date:
Subject: Re: [HACKERS] <> join selectivity estimate question