Re: PUBLIC:Re: Duplicate check constraints on the same column

Keith Boulton wrote:
>
> I just experimented with this and it happens exactly as you said. I'm
> surprised that Oracle doesn't warn you if you add a constraint with
> the same text as a pre-existing constraint.

Obviously Oracle allows duplicate check constraints. Note that you can't modify a check constraint, you have do drop it first and then add it with new check values. It is treated like a table constrant i the ALTER TABLE syntax.
SQL reference tells you:
"If you create multiple CHECK constraints for a column, design them carefully so their purposes do not conflict. Oracle7 does not verify that CHECK conditions are not mutually exclusive. "

Regards,
Roland Received on Sat Nov 29 1997 - 00:00:00 CST