130 - Information Systems

Question 1

What are the benefits of using databases and name 5 main properties

Answer 1

They are organised collections of data. Main properties are:

1. Scalability
2. Storage
3. Data handling
4. Access control
5. Security

Question 2

What is a DBMS?

Answer 2

Database Management System is software that allows users to edit data in a database.

Question 3

What are the 3 important things that the DBMS manages?

Answer 3

1. The data
2. The database engine - allows data to be accessed, locked and modified.
3. The database schema - defines the databases logical structure.

Question 4

3 main components of the Relational Data Model

Answer 4

1. Data structure
2. Data manipulation
3. Data integrity

Question 5

How do you create and manipulate the structure of databases? (Name 4)

Answer 5

1. Structures Query Language (SQL) - based on relational algebra
2. Data Definition Language (DDL) - used to define structures
3. Data Manipulation Language (DML) - used to manipulate data.
4. Data Control Language (DCL) - used to control access to data in a database.

Question 6

What is Relational Integrity?

Answer 6

It controls what can and can’t be done in a database.

Question 7

What are the components of Relational Data Integrity?

Answer 7

1. Domain integrity - Attributes have a name and a domain. Govern values in coins and restrict them to data types.
2. Entity integrity - Controls rows in tables.
3. Referential Integrity - Maintains relationships between tables.

Question 8

From referential Integrity, what is the parent key?

Answer 8

A foreign key that identifies a key in another relation.

Question 9

What is the main model for storing and processing data?

Answer 9

The main model used for storing and processing data is the relational data model where data is organised into sets.