DBMS Chapter 3

Question 1

Table (Informal)

Answer 1

Relation (Formal)

Question 2

Column (Informal)

Answer 2

Attribute/Domain (Formal)

Question 3

Row (Informal)

Answer 3

Tuple (Formal)

Question 4

Values in a Column (Informal)

Answer 4

Domain (Formal)

Question 5

Populated Table (informal)

Answer 5

Extension (Formal)

Question 6

Sets

Answer 6

A set is any well-defined list, collection, or class of objects.

Question 7

Subsets

Answer 7

If every element in a set A is also a member of a set B, then A is called a subset of B.

Question 8

Union

Answer 8

The union of sets A and B is the set of all elements which belong to A or to B or to both. A∪B

Question 9

Relation

Answer 9

A table of values (a set of rows, or set of columns)

Question 10

Strength of Relational Approach

Answer 10

Comes from the formal foundation provided by the theory of relations

Question 11

Tuple

Answer 11

An ordered set of values

Question 12

Domain

Answer 12

An atomic set of values

Question 13

Constraints (Definition)

Answer 13

Conditions that must hold on all valid relation instances

Question 14

3 Relational Integrity Constraints

Answer 14

1. Key Constraints 2. Entity Integrity Constraints 3. Referential Integrity Constraints

Question 15

Key Constraint

Answer 15

Super Key, Candidate Key, Primary Key

Question 16

Entity Integrity

Answer 16

The primary key attributes PK of each relation schema R in S cannot have null values in any tuple of r(R).

Question 17

Referential Integrity

Answer 17

Used to specify a relationship among tuples in two relations

Question 18

Converting ERD to relational schema

Answer 18

Question 19

Update Operations on Relations

Answer 19

• INSERT a tuple.
• DELETE a tuple.
• MODIFY a tuple.