Re: Materialized views WIP patch - Mailing list pgsql-hackers

From Kevin Grittner
Subject Re: Materialized views WIP patch
Date
Msg-id 1361397816.6744.YahooMailNeo@web162903.mail.bf1.yahoo.com
Whole thread Raw
In response to Re: Materialized views WIP patch  (Peter Eisentraut <peter_e@gmx.net>)
Responses Re: Materialized views WIP patch
List pgsql-hackers
Peter Eisentraut <peter_e@gmx.net> wrote:
> On 2/20/13 2:30 PM, Kevin Grittner wrote:
>>> Are there TRUNCATE triggers on materialized views?
>> No.  Nor SELECT, INSERT, UPDATE, or DELETE triggers.  You can't
>> create a trigger of any type on a materialized view.  I don't
>> think that would interfere with event triggers, though.
>
> More generally, I would consider the invalidation of a
> materialized view a DDL command, whereas truncating a table is a
> DML command.

The force of that assertion is somewhat undercut by the fact that
the ExecuteTruncate() function does exactly what needs to be done
to discard the data in a materialized view and make it appear as
non-scannable.  Even if we dress it up with different syntax, it's
not clear that we wouldn't build a TruncateStmt in the parser and
pass it through exactly the same execution path.  We would just
need to look at the relkind to generate a different command tag.

> This has various implications with triggers, logging,
> permissions.  I think it's not good to mix those two.

Could you give a more concrete example of where you see a problem?

--
Kevin Grittner
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



pgsql-hackers by date:

Previous
From: Alvaro Herrera
Date:
Subject: Re: PATCH: Split stats file per database WAS: autovacuum stress-testing our system
Next
From: Tatsuo Ishii
Date:
Subject: Re: Materialized views WIP patch