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
adefault 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;