Question

When performing union, intersection, or difference operations on relations R and S, they must be type compatible. That is, ______

Select one:
a. The domain of corresponding attributes of R and S must be compatible
b. The names of attributes of R and S must be the same
c. R and S must have the same number of attributes
d. R and S must have the same number of attributes and the domain of corresponding attributes of R and S must be compatible

Answer 1

For union, intersection, or difference operations, relations R and S must be type compatible, which requires the same number of attributes and compatible attribute domains.

Step-by-step explanation:

When performing set operations such as union, intersection, or difference on relations R and S in the context of a database, it is essential that these relations be type compatible.

Key Conditions for Operations on Relations

The correct answer to the question is:

d. R and S must have the same number of attributes and the domain of corresponding attributes of R and S must be compatible

This means that not only must R and S have the same number of attributes, but each corresponding attribute must also have the same data type or a compatible one, allowing for the operations to be performed correctly.