is pivoted phones view updateable?

Tchuzhie Giri wrote:
> It is not "OK" so long as one does not have your rules of updatability.
> You put a pile of symbols on the pile of symbols: it does not have
> sense without the rules. Please provide the rules, simple examples
> and then one can go to more complex examples.

Given two relation variables

Y(n, #) -- aka WorkPhones(name, number) and
Z(n, #) -- aka CellPhones(name, number)

and two relation constants

A = {(t='work')}

and

B = {(t='cell')}

is the view

X = (Y /\ A) \/ (Z /\ B) -- aka ConsolidatedPhones

updateable? There is no minus operator involved. The only two RA operators are join /\ and union \/. Received on Thu Nov 09 2006 - 13:30:34 CST