"Paul Vernon" <paul.vernon_at_ukk.ibmm.comm> wrote in message
news:bpggsg$1dss$1_at_gazette.almaden.ibm.com...
> "Serge Rielau" <srielau_at_ca.eye-bee-m.com> wrote in message
> news:bpfnq8$csd$1_at_hanover.torolab.ibm.com...
> > Very good points.
> > In development we call this "syntactic sugar". As a developer I'm
> > responsible to implement orthogonality (i.e. supply RANK() OVER()),
> > howvere, said education gap ,plus the complexity coming out of the
> > optimizer strongly encourages "shorthands" for the most common
> constraucts.
> >
> > Let me defend my position :-)
> > In the latest version of DB2 we increased orthogonality by allowing
> > INSERT, UPDATE and DELETE in the FROM clause. I.e. we declare these
> > operators to return sets.
>
> Indeed, and I highly applaud you guys for doing so. I've not used them in
> anger as yet, but from what I've seen they do look to be nicely orthogonal
> (or at least as nicely orthogonal as SQL lets you get to).
> Interestingly, such select from update is not mentioned in the relational
> language I know most about (i.e. Tutorial D), and is one (not
insignificant)
> example of where lack of expressability
D nests relational expressions within variable operations and nests variable
operations within variable operations. It does not, and should not, nest
variable operations within value operations. Value operations with
side-effects is a really, really, really bad idea.
Received on Wed Nov 19 2003 - 15:55:41 CST
