Re: Pg_upgrade and toast tables bug discovered

On Thu, Sep 4, 2014 at 3:35 PM, Bruce Momjian <bruce@momjian.us> wrote:
>> At any rate, I've additionally observed that the relation which is blowing up
>> pg_upgrade is a VIEW in the source cluster but gets created as a TABLE in the
>> upgraded cluster, which may better explain why it had no toast table before and
>> now it does.  Is this some kind of expected behavior for views?
>
> Uh, it certainly should not be creating a table instead of a view,
> though it will get a pg_class entry.

Actually, there's a way this can happen.  If you create two (or more)
views with circular dependencies between them, then pg_dump will emit
commands to create one of them as a table first, then create the
others as views, then convert the first table to a view by adding a
_SELECT rule to it.

If pg_upgrade's logic can't cope with that, that's a bug in
pg_upgrade, because there's no other way to restore views with
circular dependency chains.

-- 
Robert Haas
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