Re: ALTER TABLE ... REPLACE WITH

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Csaba Nagy <ncslists@googlemail.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Josh Berkus <josh@agliodbs.com>, pgsql-hackers@postgresql.org
Date: 2010-12-15T15:50:13Z
Lists: pgsql-hackers
On Wed, 2010-12-15 at 12:17 +0100, Csaba Nagy wrote:

> But one problem would be when the replaced table is the _parent_ for a
> foreign key relationship. I don't think you can have that constraint
> pre-verified on the replacement table and simply replacing the content
> could leave the child relations with orphans. 

Good point.

The only sensible way to handle this is by putting the FK checks into
check pending state (as discussed on a different thread).

We would probably need to disallow FKs with DELETE or UPDATE CASCADE
since it would be difficult to execute those.

-- 
 Simon Riggs           http://www.2ndQuadrant.com/books/
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