Is there a commercial RDBMS that allows one to create indices on
views?
I'm asking this partly because of BCNF.
A typical BCNF problem is (where -> is a FD)
A, B->C
C -> B
which becomes the following relations
R_A [_A_, _C_]
R_B [_C_, B]
where _X_ denotes an attribute in the primary key
since
R [_A_,_C_,B] is not in 2NF
But there's an additional constraint where the equijoin of R_A and R_B
on C would have the candidate key A,B.
Is there a way to express this last constraint (i.e., a candidate key
on a view) in an implementation system?
Cecil Chua
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