Question

EXCEPT in SQL is analogous to
(1) Intersection operator of relational algebra
(2) Join operator of relational algebra
(3) Difference operator of relational algebra
(4) Cartesian product operator of relational algebra

Answer 1

3rd option is correct

Answer 2

Answer:

EXCEPT in SQL is analogous to Difference operator of relational algebra

Explanation:

• Intersection operator is used to select common rows (tuples) from two tables (relations) and it is denoted by ∩ symbol .

• Join operation is used to combine the relation R1 and R2 with respect to a condition. Join operator is denoted by ⋈.

• Difference  (-) operator - Difference operator is denoted by - symbol. relation1 - relation2 will result into a relation where the tuple in relation1 and not in relation2 are present.

• The Cartesian Product, also called the CROSS PRODUCT or CROSS JOIN, is an operator which works on two sets. Cartesian product operator combines the tuples of one relation with all the tuples of the other relation.