Database Questions and Answers – Relational Database and Database Schema
This set of Database Multiple Choice Questions & Answers (MCQs) focuses on “Relational Database and Database Schema”.
1. The term attribute refers to a ___________ of a table.
Explanation: Attribute is a specific domain in the relation which has entries of all tuples.
2. For each attribute of a relation, there is a set of permitted values, called the ________ of that attribute.
Explanation: The attribute’s values must be present in the domain. A domain is a set of values that can be used.
3. Database __________ which is the logical design of the database, and the database _______ which is a snapshot of the data in the database at a given instant in time.
a) Instance, Schema
b) Relation, Schema
c) Relation, Domain
d) Schema, Instance
Explanation: Instance is an instance of time and schema is a representation.
Here the course_id,sec_id and semester are __________ and course is a _________
a) Relations, Attribute
b) Attributes, Relation
c) Tuple, Relation
d) Tuple, Attributes
Explanation: The relation course has a set of attributes course_id,sec_id,semester .
5. Department (dept name, building, budget) and Employee (employee_id, name, dept name, salary)
Here the dept_name attribute appears in both the relations. Here using common attributes in relation schema is one way of relating ___________ relations.
a) Attributes of common
b) Tuple of common
c) Tuple of distinct
d) Attributes of distinct
Explanation: Here the relations are connected by the common attributes.
6. A domain is atomic if elements of the domain are considered to be ____________ units.
7. The tuples of the relations can be of ________ order.
Explanation: The values only count. The order of the tuples does not matter.
8. A relational database consists of a collection of
Explanation: Fields are the relation or table’s columns. Each row in a relation is referred to as a record. The limits of a relationship are known as keys.
9. A ________ in a table represents a relationship among a set of values.
Explanation: There is only one set of values in a column. Constraints are keys, and a row is a collection of attributes. An entry is nothing more than a piece of information.
10. The term _______ is used to refer to a row.
Explanation: Tuple is an entry in a relation that has numerous fields as attributes.