Re: pg_dump --binary-upgrade vs. ALTER TYPE ... DROP ATTRIBUTE

From: Peter Eisentraut <peter_e(at)gmx(dot)net>
To: Noah Misch <noah(at)leadboat(dot)com>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: pg_dump --binary-upgrade vs. ALTER TYPE ... DROP ATTRIBUTE
Date: 2011-03-30 16:55:43
Message-ID: 1301504143.31317.3.camel@vanquo.pezone.net
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On tis, 2011-03-29 at 17:50 -0400, Noah Misch wrote:
> Fixing that looks clear enough, but the right fix for the typed table
> issue is less clear to me. The pg_attribute tuples for a typed table
> will include any attributes dropped from the parent type after the
> table's creation, but not those attributes dropped before the table's
> creation. Example:
>
> create type t as (x int, y int);
> create table is_a of t;
> alter type t drop attribute y cascade;
> create table is_a2 of t;
> select * from pg_attribute where attrelid = 'is_a'::regclass;
> select * from pg_attribute where attrelid = 'is_a2'::regclass;
>
> To reproduce that catalog state, the dump would need to create the
> type, create all typed tables predating the DROP ATTRIBUTE, and
> finally create typed tables postdating the DROP ATTRIBUTE. That
> implies an extra dump entry for the DROP ATTRIBUTE with the
> appropriate dependencies to compel that order of events. Is
> there a better way?

Maybe we could just copy the dropped attributes from the type when the
table is created. That might be as simple as removing the

if (attr->attisdropped)
continue;

in transformOfType().

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Peter Eisentraut 2011-03-30 17:41:31 pg_upgrade and PGCLIENTENCODING
Previous Message Peter Eisentraut 2011-03-30 16:50:12 Re: Typed-tables patch broke pg_upgrade