Yateen Joshi 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?
Thanks and regards,
Yateen V. Joshi
You could try:
id INT PRIMARY KEY NOT NULL DEFAULT(1) CHECK (id = 1),
Tim