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* Populate unique column with default value
@ 2007-10-01 15:24 Jon Horsman <horshaq@gmail.com>
2007-10-01 15:33 ` Re: Populate unique column with default value Jon Horsman <horshaq@gmail.com>
2007-10-01 15:39 ` Re: Populate unique column with default value Rodrigo De Le� <rdeleonp@gmail.com>
0 siblings, 2 replies; 4+ messages in thread
From: Jon Horsman @ 2007-10-01 15:24 UTC (permalink / raw)
To: pgsql-sql
Hey,
I'm updating the user table in our db to have a new column "username"
as follows.
ALTER TABLE usertable ADD COLUMN username varchar(64)
UPDATE usertable SET username='<extension of current row>' WHERE username ISNULL
ALTER TABLE usertable ALTER COLUMN username SET NOT NULL
ALTER TABLE usertable ADD CONSTRAINT usertable_username_key UNIQUE(username)
I want to essentially do what i have above but need to populate the
username field with some unique value so that the last ALTER will run.
I have another column in this table that is unique, an phone
extension, and am hoping to use this as a default username. Is there
an elegant way i can set the username to be the extension of the
current row or should i just write a little loop that goes threw and
populates my username with the users extension manually for each user
in my db and then run the last ALTER.
Thanks,
Jon.
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Populate unique column with default value
2007-10-01 15:24 Populate unique column with default value Jon Horsman <horshaq@gmail.com>
@ 2007-10-01 15:33 ` Jon Horsman <horshaq@gmail.com>
1 sibling, 0 replies; 4+ messages in thread
From: Jon Horsman @ 2007-10-01 15:33 UTC (permalink / raw)
To: pgsql-sql
I guess what i'm looking for is something like the following, but i
don't know how i'd do it.
"UPDATE usertable SET username='SELECT extension FROM usertable WHERE
id=<current row>' WHERE username ISNULL",
Is this possible?
Thanks,
Jon.
On 10/1/07, Jon Horsman <horshaq@gmail.com> wrote:
> Hey,
>
> I'm updating the user table in our db to have a new column "username"
> as follows.
> ALTER TABLE usertable ADD COLUMN username varchar(64)
> UPDATE usertable SET username='<extension of current row>' WHERE username ISNULL
> ALTER TABLE usertable ALTER COLUMN username SET NOT NULL
> ALTER TABLE usertable ADD CONSTRAINT usertable_username_key UNIQUE(username)
>
> I want to essentially do what i have above but need to populate the
> username field with some unique value so that the last ALTER will run.
> I have another column in this table that is unique, an phone
> extension, and am hoping to use this as a default username. Is there
> an elegant way i can set the username to be the extension of the
> current row or should i just write a little loop that goes threw and
> populates my username with the users extension manually for each user
> in my db and then run the last ALTER.
>
> Thanks,
>
> Jon.
>
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Populate unique column with default value
2007-10-01 15:24 Populate unique column with default value Jon Horsman <horshaq@gmail.com>
@ 2007-10-01 15:39 ` Rodrigo De Le� <rdeleonp@gmail.com>
2007-10-01 15:51 ` Re: Populate unique column with default value Jon Horsman <horshaq@gmail.com>
1 sibling, 1 reply; 4+ messages in thread
From: Rodrigo De Le� @ 2007-10-01 15:39 UTC (permalink / raw)
To: Jon Horsman <horshaq@gmail.com>; +Cc: pgsql-sql
On 10/1/07, Jon Horsman <horshaq@gmail.com> wrote:
> ... Is there an elegant way i can set the username
> to be the extension of the current row ...
UPDATE usertable
SET username = extension
WHERE username IS NULL;
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Populate unique column with default value
2007-10-01 15:24 Populate unique column with default value Jon Horsman <horshaq@gmail.com>
2007-10-01 15:39 ` Re: Populate unique column with default value Rodrigo De Le� <rdeleonp@gmail.com>
@ 2007-10-01 15:51 ` Jon Horsman <horshaq@gmail.com>
0 siblings, 0 replies; 4+ messages in thread
From: Jon Horsman @ 2007-10-01 15:51 UTC (permalink / raw)
To: Rodrigo De Le� <rdeleonp@gmail.com>; +Cc: pgsql-sql
> On 10/1/07, Jon Horsman <horshaq@gmail.com> wrote:
> > ... Is there an elegant way i can set the username
> > to be the extension of the current row ...
>
> UPDATE usertable
> SET username = extension
> WHERE username IS NULL;
Hmm, that simple eh, don't I feel stupid =)
Thanks a ton for the quick response.
Jon.
^ permalink raw reply [nested|flat] 4+ messages in thread
end of thread, other threads:[~2007-10-01 15:51 UTC | newest]
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2007-10-01 15:24 Populate unique column with default value Jon Horsman <horshaq@gmail.com>
2007-10-01 15:33 ` Jon Horsman <horshaq@gmail.com>
2007-10-01 15:39 ` Rodrigo De Le� <rdeleonp@gmail.com>
2007-10-01 15:51 ` Jon Horsman <horshaq@gmail.com>
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