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.

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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.
>

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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;

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> 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.

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