RE: Check constraints was: Imbedded SQL vs Sequence object

I really have a hard time with edits in a before trigger, in a

maintenance

program, and in a constraint. What if the before trigger thinks the
maintenance program will handle it, and the maintenance program thinks

the

constraint will handle it?

I view it the other way. It's not that the DB (constraint) should handle
the edit, it's that it's a last-line-of-defense against any program that
doesn't handle the edit.

Inserting data into a table without checking the constraints much
earlier in the program stack is just silly. Sure, you can handle the
error, decode the constraint name, and somehow notify the user in a
friendly manner from 7 program calls deeper in the stack, or you can
just check for the error in the UI in the first place and give the user
a friendly message.

The point of a constraint is to tell the db how to protect itself from
_any_ unchecked updates. Say, DFU, DBU, ODBC, whatever.

-Walden

--
Walden H Leverich III
Tech Software
(516) 627-3800 x3051
WaldenL@xxxxxxxxxxxxxxx
http://www.TechSoftInc.com

Quiquid latine dictum sit altum viditur.
(Whatever is said in Latin seems profound.)