Date: Wed, 18 Apr 2018 14:37:11 +0300
From: Arthur Zakirov <a.zakirov@postgrespro.ru>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: [HACKERS] proposal: schema variables
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On Tue, Apr 17, 2018 at 06:28:19PM +0200, Pavel Stehule wrote:
> I though about it, and I am inclined to prefer pg_class instead separate
> tables.
> 
> It true, so there are lot of "unused" attributes for this purpose, but
> there is lot of shared attributes, and lot of shared code. Semantically, I
> see variables in family of sequences, tables, indexes, views. Now, it
> shares code, and I hope in next steps more code can be shared -
> constraints, triggers.
> 
> There are two objective arguments for using pg_class:
> 
> 1. unique name in schema - it reduces risk of collisions
> 2. sharing lot of code
> 
> So in this case I don't see well benefits of separate table.

Understood. I haven't strong opinion here though. But I thought that
pg_class approach may limit extensibility of variables.

BTW:
- there is unitialized variable 'j' in pg_dump.c:15422
- in tab-complete.c:1268 initialization needs extra NULL before
  &Query_for_list_of_variables

Also I think makeRangeVarForTargetOfSchemaVariable() has non friendly
argument names 'field1', 'field2', 'field2'.

-- 
Arthur Zakirov
Postgres Professional: http://www.postgrespro.com
Russian Postgres Company