Обсуждение: BUG with UNIQUE clause

> The UNIQUE constraint doesn't work on a field if I use a DEFAULT
> clause on a table.
> The following table works with UNIQUE constraint:
> but this one accept several same tcnom value:
> create table cltclt001(
>   tcid int2 default nextval('cltcls001'),
>   tcnom text unique
> );
> What's wrong with my table ?

Nothing. You have stumbled across a bug recently discovered by Mark
Dalphin <mdalphin@amgen.com> in the parser. It was repaired in the
source trees 1999-08-15 so will appear in v6.5.2 (any day now) and
v6.6.

postgres=> create sequence cltcls001;
CREATE
postgres=> insert into cltclt001 (tcnom) values ('one');
INSERT 150559 1
postgres=> insert into cltclt001 (tcnom) values ('one');
ERROR:  Cannot insert a duplicate key into a unique index

I imagine that the repair is posted to the patches or hacker's mailing
list; look in the archives around that date and you should be able to
patch your existing recent system.

Good luck.

                   - Thomas

--
Thomas Lockhart                lockhart@alumni.caltech.edu
South Pasadena, California

"=?iso-8859-1?Q?St=E9phane_FILLON?=" <fillons@offratel.nc> writes:
> The UNIQUE constraint doesn't work on a field if I use a DEFAULT clause
> on a table.

This sounds closely related to a fix that Thomas Lockhart just made.
IIRC the complained-of symptom was that PRIMARY KEY on one column plus
UNIQUE on another didn't work, but the real problem was that PRIMARY
KEY implies UNIQUE and the table declaration code was getting confused
by two different UNIQUE columns in one table.  It could be that his fix
addresses your problem too.  Check the pghackers archives for the
last couple weeks to find the patch.

            regards, tom lane