Which of the following relational operators is are associati

Which of the following relational operator(s) is (are) associative?

a. select

b. project

c. union

d. intersect

e. Cartesian product

Solution

Select and project operation also associative operations.

Union, Intersection and cartesian product are associative as

R union (S union T) = (R union S) union T

R intersect (S intersect T) = (R intersect S) intersect T

R X (S X T) = (R X S) X T

Hence, all of the given operator are associative.