SGreen@stripped wrote:
> I don't see how you can possibly hope to satisfy two mutually dependent
> constraints at the exact same time. It's a chicken-and-egg scenario. If you
> can't create your vacancy record first (to get its PK value) you won't be
> able to create the new record in your supervision table.
(..)
> It's not hard to do what you want, but it requires logic external to the
> storage engine itself to enforce that kind of relationship.
In databases this is usually solved in the storage engine itself
by deferring constraint checking to transaction commit.
Unfortunately, MySQL doesn't offer deferred constraints (haven't
seen them on the ToDo list either).
Jochem
