currval = currval+1

On Wed, Jun 1, 2011 at 9:27 AM, salah jubeh <s_jubeh@yahoo.com> wrote:

I have the following SQL statements

BEGIN;
-- account_id is a sequence
INSERT INTO account (name) VALUES ('test customer'||random()::text);
-- account_id is a foreign key
INSERT INTO account_detail (account_id,......)  VALUES ((SELECT * from
currval('account_acccount_id_seq')), ........);
COMMIT;

ERROR:  insert or update on table "account_detail" violates foreign key
constraint ...

I have executed the above without a transaction but in the same session, and
the issue was that the current value of the account points to the curval + 1

I have solved the above by subtracting 1 in the second insert statement. Why
I am having this problem, I have used current value many time and this is
the first time I have this behavior.

works for me -- are you sure you don't have a trigger or something
else going on behind the scenes?

merlin

I have some rules on the table and I have dropped them and everything went fine.
the rule is as follow

CREATE OR REPLACE RULE status_change_ins AS
ON INSERT TO account DO INSERT INTO account_status_change_log (account_id,
account_status_id, status_change_date)

VALUES (new.account_id, new.account_status_id, now());

I do not know what is happing here, but this is a strange behavior.

Regards

________________________________
From: Merlin Moncure <mmoncure@gmail.com>
To: salah jubeh <s_jubeh@yahoo.com>
Cc: pgsql-general@postgresql.org
Sent: Wed, June 1, 2011 4:54:36 PM
Subject: Re: [GENERAL] currval = currval+1

On Wed, Jun 1, 2011 at 9:27 AM, salah jubeh <s_jubeh@yahoo.com> wrote:

I have the following SQL statements

BEGIN;
-- account_id is a sequence
INSERT INTO account (name) VALUES ('test customer'||random()::text);
-- account_id is a foreign key
INSERT INTO account_detail (account_id,......) VALUES ((SELECT * from
currval('account_acccount_id_seq')), ........);
COMMIT;

ERROR: insert or update on table "account_detail" violates foreign key
constraint ...

I have executed the above without a transaction but in the same session, and
the issue was that the current value of the account points to the curval + 1

I have solved the above by subtracting 1 in the second insert statement. Why
I am having this problem, I have used current value many time and this is
the first time I have this behavior.

works for me -- are you sure you don't have a trigger or something
else going on behind the scenes?

merlin

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On Wed, Jun 1, 2011 at 10:22 AM, salah jubeh <s_jubeh@yahoo.com> wrote:

I have some rules on the table and I have dropped them and everything went
fine. the rule is as follow

CREATE OR REPLACE RULE status_change_ins AS
    ON INSERT TO account  DO  INSERT INTO account_status_change_log
(account_id, account_status_id, status_change_date)
  VALUES (new.account_id, new.account_status_id, now());

I do not know what is happing here, but this is a strange behavior.

'rules suck' is the problem :(. uncontrollable re-execution of
volatile functions is just *one* issue with them. good news: 9.1
completely fixes this with view update triggers. In the meantime,
consider dropping the update rule and making a functions which does
the delete and updates the log, or doing it in the client.

merlin

salah jubeh <s_jubeh@yahoo.com> writes:

I have some rules on the table and I have dropped them and everything went fine.

Rules are macros, and have the usual issues with multiple evaluations of
multiply-referenced arguments.

CREATE OR REPLACE RULE status_change_ins AS
ON INSERT TO account DO INSERT INTO account_status_change_log (account_id,
account_status_id, status_change_date)
VALUES (new.account_id, new.account_status_id, now());

You'd be far better off doing that with a trigger.

regards, tom lane