The number of superkeys of R is:
A. 2
B. 7
C. 10
D. 12
Answer:A
The number of superkeys of R is:
A. 2 B. 7 C. 10 D. 12
Explanation:A superkey is a combination of columns that uniquely identifies any row within a relational database management system (RDBMS) table. 7. Suppose we wish to find the ID’s of the employees that are managed by people who are managed by the employee with ID 123. Here are two possible queries: