Explanation:Union just combines all the values of relations of same attributes. 7. The most commonly used operation in relational algebra for projecting a set of tuple from a relation is
A. Join
B. Projection
C. Select
D. Union
Answer:A
Explanation:Union just combines all the values of relations of same attributes. 7. The most commonly used operation in relational algebra for projecting a set of tuple from a relation is
A. Join B. Projection C. Select D. Union
Explanation:Select is used to view the tuples of the relation with or without some constraints. advertisements