Revision

Question 1

List the levels in which data can be controlled.

Answer 1

Relevant
Accurate
Unique
Timely
Unambiguous
Complete

Question 2

Advantages of DBMS.

Answer 2

Improved data sharing
Better Data integration
Less data inconsistency

Question 3

Fully explain data redundancy.

Answer 3

Redundant data results in data
inconsistencies and can lead to data anomalies. There are 3 types of data anomalies, update anomalies (occurs when an inconsistency is introduced as changes are made to existing records, insert anomaly (occurs when an inconsistency is introduced when entering new records, deletion anomaly (occurs when an inconsistency is introduced when deleting
records).

Question 4

List the functions of DBMS. DDS

Answer 4

Data dictionary management
Data storage management
Security management
Data transformation

Question 5

What is the advantage of RDBMS?

Answer 5

Hides complexities of relational model from user.

Question 6

What is entity integrity?

Answer 6

It is a field or fields that
uniquely identifies each record and contains no nulls.

Question 7

What is referential integrity?

Answer 7

It is a field or fields that reference a primary key ] in another
table, contains only values found in the primary table or nulls.