Re: Row locking and serializability

Not entirely.

Code you write has to follow the rules of read consistency, uncommitted data etc.

Actions performed by Oracle whilst enforcing declarative integrity constraints may, internally, choose to break these rules - consequently there are some side-effects of pk/fk constraints particularly which can be used to effect manual serialisability.

I doubt if I would use this method in the case of your problem of the airline booking with 100 seats per plane, of course. The trivial solution to that is to record the number of seats currently booked as a column on the plane row and write triggers to maintain that number as seats are booked.

--

Jonathan Lewis
Yet another Oracle-related web site: www.jlcomp.demon.co.uk

iggy_fernandez_at_my-deja.com wrote in message <7lrn5g$16f$1_at_nnrp1.deja.com>...
>
>Don't integrity constraints act simply as extensions of your
>application program and hence become subject to the Oracle concurrency
>model, profiting from its strengths and constrained by its weaknesses?
>
Received on Wed Jul 07 1999 - 04:51:26 CDT