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

84) Which structure is the hierarchical model based

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

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

87) Why do we have to create a primary index on a primary key