Re: BUG #3910: Incorrect behavior of UPDATE statement on tables with constraints UNIQUE/PRIMARY KEY

[Alvaro Herrera <alvherre(at)commandprompt(dot)com>]

Dmitry Afanasiev wrote:

> Constraints must be checked AFTER updating ALL of rows, but really after
> every row.
> For illustrate try this simple sql script:
> CREATE TABLE n(n INTEGER PRIMARY KEY);
> INSERT INTO n VALUES(1);
> INSERT INTO n VALUES(2);
> INSERT INTO n VALUES(3);
> UPDATE n SET n = n + 1;

Yes.  This is a known problem.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support