From X to Y and vice-versa

[Sznajder ForMailingList <bs...@gmail.com>]

Hi

I try to build a right schema for my table.

I have tuples {X_i, Y_j} and I have to answer to two kinds of queries:

Y_j getYvalue(X_i) : given a value X_i, return me the corresponding value
Y_j

X_i getYvalue(Y_j) : given a value Y_j, return me the corresponding value
X_i


The easiest way would be to define two tables : one with Keys {X_i} and the
second with Keys {Y_j}

Does it exist a better way?

Thanks!

Benjamin