Re: ALTER TABLE ... ALTER CONSTRAINT

On 2013-06-08 21:45:24 +0100, Simon Riggs wrote:
> While fiddling with FK tuning, it was useful to be able to enable and
> disable the DEFERRED mode of constraints.
>
> That is not currently possible in SQL, so I wrote this patch. Without
> this you have to drop and then re-add a constraint, which is
> impractical for large tables.
>
> e.g.
> CREATE TABLE fktable (id integer, fk integer REFERENCES pktable (id));
>
> ALTER TABLE foo
> ALTER CONSTRAINT fktable_fk_fkey DEFERRED INITIALLY IMMEDIATE;
>
> Includes docs and tests.
>
> Currently works for FKs only. Potentially other constraints can be
> supported in future.

I haven't looked at the patch in detail, but I am very, very much in
favor of the feature in general… I have wished for this more than once,
and it certainly cost me more time working around it than it would have
cost to implement it.

Thanks,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services