Question

Which of the following are the constraints of database schemas?
a. Domain constraints, Key constraints, Entity integrity constraints, Referential integrity constraints
b. Domain constraints, Data constraints, Entity integrity constraints, Referential integrity constraints

• A. Only "a"
• B. Only "b"
• C. Both "a" and "b"
• D. None of the above

Answer 1

The correct option is A Only "a"

A relational database schema is a set of relation schemas and a set of integrity constraints. There are four different constraints, which can be specified on relational database. These are: domain constraints, key constraints, entity integrity constraints, referential integrity constraints.