Question

Which of the following statement(s) is/are true?

A. Selection operation yields horizontal subset of a relation.
B. Selection operation yields vertical subset of a relation.
C. Union operator can work on relation with different degree.
D. Intersection and Cartesian product operations are not binary.
E. A record is a column on a datasheet.

• 1. A only
• 2. B only
• 3. C and E only
• 4. D and E only

Hint:

Selection operation allows us to filter rows from a relation, which is typically considered a horizontal subset.

Answer 1

The Correct Option is A

- Statement A is true, as the selection operation yields horizontal subsets.
- Statement B is false, as selection operates horizontally.
- Statement C is false, union can only work with relations of the same degree.
- Statement D is false, intersection and Cartesian product are binary operations.
- Statement E is false; a record is a row, not a column.