On Fri, Aug 27, 2004 at 13:32:07 +0530,
Yateen Joshi <yjoshi@starentnetworks.com> wrote:
> Hi,
>
> I have got a table which is supposed to contain only one row. It does
> not have any primary keys defined.
> So, essentially, when a new insert happens in that table, I would like
> it (the insert) to fail if there is already a row existing in that
> table.
> How can I do that? Can I add any constraints? Or do I need to write a
> separate trigger for the same?
A simple way to force this is to add a primary key and a constraint
that forces the primary key to be a particular value.