Databases MCQ with Answers

Databases MCQ with Answers

82) Consider a relational table with a single record for each registered student with the following attributes.
1. Registration Num: Unique registration of each registered student.
2. UID Unique identity number, unique at the national level for each citizen.
3. Name: Name of the student.
4. BankAccount Num: Unique account number at the bank. A student can have multiple account or joint accounts.This attribute stores the primary account number.
5. Hostel_Room: Room number of th

Answer is:

BankAccount Num is a candidate key.

83) The following functional dependencies hold for relation R(A, B, C) and S(B, D, E) B —> A, A —> C , the relation R contains 200 tuples and relation S contains 100 tuples. What is maximum number of tuples possibles in natural join R and S ?

Answer is:

100

84) Which structure is the hierarchical model based

Answer is:

Tree

85) In the relational model, the number of attributes and number of tuples in a relation are termed as and ____respectively

Answer is:

Degree, cardinality

86) In domain relational calculus we create a variable for every

Answer is:

Column

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