Hi,
if you define the foreign key with "ON UPDATE CASCADE" you don't have to
worry about updating table2.
Would look like this:
the tables:
create table table1 (id int primary key, col1 int);
create table table2 (id int primary key references table1(id) ON UPDATE
CASCADE, col2 int);
the (one and only) UPDATE:
update table1 set id = 1001 where id = 1;
Your 2nd UPDATE will be done automatically.
The other solution for your problem is less elegant.
First INSERT a new record ( 1001 , x) for each row (1, x) in table1 into
table1
then UPDATE table2
last DELETE all records (1, x) from table1
Would look like:
BEGIN;
INSERT INTO table1 SELECT 1001, col1 FROM table1 WHERE id=1;
UPDATE table2 set id = 1001 WHERE id = 1;
DELETE FROM table1 where id=1;
COMMIT;
Hope this would help,
Andre
----- Original Message -----
From: Steve SAUTETNER
To: pgsql-general@postgresql.org
Sent: Thursday, July 26, 2001 11:19 AM
Subject: [GENERAL] concurent updates
hi everybody !
I've got a little problem when updating a primary key in two table
where the primary key of the one is a foreign key from the second :
here are the 2 tables :
create table table1 (id int primary key, col1 int);
create table table2 (id int primary key references table1(id), col2 int);
and the 2 updates :
1) update table2 set id = 1001 where id = 1;
2) update table1 set id = 1001 where id = 1;
i can't execute them separately because of an integrity constraint
violation.
i've got the same error in a BEGIN / COMMIT block containing the updates.
Does any one see how two help me ?
thanks.
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