Re: [SQL] How to Convert Integer to Serial

On Fri, Oct 29, 2010 at 3:48 PM, venkat <ven(dot)tammineni(at)gmail(dot)com> wrote:

> Dear All,
>
> I want to convert integer datatype to serial datatype.. is that
> possible.Please let me know.
>
>
I don't think ALTER TABLE will let you do that... so the best way to achieve
the same is:

- Create a sequence for the column (set the start of sequence according to
the values you got already in the column)
- Now set this sequence as the default value for that specific column which
you need to ALTER like this:

ALTER TABLE tablename ALTER COLUMN columnname
SET DEFAULT nextval('newsequence'::regclass);

--
Shoaib Mir
http://shoaibmir.wordpress.com/