Re: How to setup a column constraint for an integer type? Default 0 if not defined

[John R Pierce <pierce@xxxxxxxxxxxx>]

Wang, Mary Y wrote:
> Hi,
>
>
> I'm trying to port some source code to Postgres 8.3.8 and have been encountering some surprises :-(
> I would like to set up a column constraint for an integer type, so that when the value is undefined, it would assign a default value of 0 to that column.
> How would I do that in 8.3.8?  Please provide an example.
>   

when you say, 'value is undefined' do you mean, if an insert is done 
without specifying that field ?

in that case, ou wouldn't use a constraint, you'd use a DEFAULT value, 
like...

   CREATE TABLE tblname (
                  ....
                 somefield INTEGER DEFAULT 0,
                  ....
                  );

or, if the table already exists...

   ALTER TABLE tblname ALTER COLUMN somefield SET DEFAULT 0;




--
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general