Prove that for any relation R(X,Y)
Select Select(R (X=x0) (Y=y0))) =
Select (R(X=x0) and Y=y0))
What is an equivalent form of (Select(R (X=x0) or (Y=y0)))?
Select Select(R (X=x0) (Y=y0))) =
Select (R(X=x0) and Y=y0))
What is an equivalent form of (Select(R (X=x0) or (Y=y0)))?