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Thread:

From
"A.M."
Date:
I have a reference which is guaranteed not to have a valid reference 
(preferably NULL) until it is processed later. How can I defer a 
reference entry so that both NULL and an actual reference are valid in 
the reference field? The processing which I speak of takes place later 
and not in the same transaction (thus making DEFERRABLE useless, 
right?). A solution I thought of is to forget keys and just make it an 
INT8 since I am also guaranteed that its referenced item is never 
deleted. But certainly, there is a more reliable way to do it, right?In summary, what I want is
 field INT8 REFERENCES sometable NULL OK

or

field INT8 CHECK(SELECT id FROM someothertable WHERE field=id)

(can I do this? this allows NULL right?)

The rule is ref2 can either be a valid reference or NULL.
CREATE TABLE thetable(ref2 INT8 REFERENCES someothertable,...
);

Thanks for any help.><><><><><><><><><
AgentM
agentm@cmu.edu

Re:

From
Tom Lane
Date:
"A.M." <agentm@cmu.edu> writes:
> In summary, what I want is

>   field INT8 REFERENCES sometable NULL OK

Er ... NULL *is* OK, unless you say
  field INT8 REFERENCES sometable NOT NULL
        regards, tom lane

Re:

From
"A.M."
Date:
Wow. That's a real head-slapper. Thanks for the quick answer!

On Friday, November 29, 2002, at 11:28  PM, Tom Lane wrote:

> "A.M." <agentm@cmu.edu> writes:
>> In summary, what I want is
>
>>   field INT8 REFERENCES sometable NULL OK
>
> Er ... NULL *is* OK, unless you say
>
>    field INT8 REFERENCES sometable NOT NULL
>
>             regards, tom lane
>
>><><><><><><><><><
AgentM
agentm@cmu.edu

Backup to data base how ?

From
ksql
Date:
This is vital for my, please send me an exampleabout like I can make me to support my database with name WAREHOUSE
-- 
Saludos de Luis,
Mi correo:                           mailto:ksql2002@yahoo.com.mx

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Re: Backup to data base how ?

From
Frank Bax
Date:
At 10:36 PM 12/11/02, ksql wrote:
>This is vital for my, please send me an example
>  about like I can make me to support my database with name WAREHOUSE


pg_dump -o -c warehouse  |  gzip  >  warehouse.gz

http://www.ca.postgresql.org/users-lounge/docs/7.3/postgres/backup.html