Hi, Thanks! The documentation is not clear. What about: "The check condition must evaluate to TRUE, FALSE or NULL. TRUE and NULL mean the operation is to be permitted, and FALSE means the operation is to be rejected. To prevent NULL in a column, use NOT NULL instead of a check constraint."
> Note: In sql standard NULL <> 1 evaluates to UNKNOWN (a third truth value) > whereas in H2 it evaluates to null (something more obscure)." Where did you read that? UNKNOWN would be a forth option (TRUE, FALSE, NULL, UNKNOWN) - which would be even more complicated. I guess it wouldn't be a big problem for H2 to support UNKNOWN, but it would be a big problem for the users of H2. Also, it would be a compatibility problem (most other databases don't support UNKNOWN). By the way, somebody told me NULL is not a value. I don't care that much, but some people are really picky about that. Regards, Thomas -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/h2-database?hl=en.
