Databases

Question 1

Manual Database

Answer 1

• A filing cabinet can be considered to be a manual database
• this is where files & folders are stored & can be retrieved by opening a drawer
• Due to the advance of technology most manual databases have been replaced by computerised databases

Question 2

Computerised Databases

Answer 2

• taken over from manual databases for the most part
• defined as the storing of files and folders electronically as a collection in tables where one related or unrelated to each other

Question 3

Definition of Databases

Answer 3

• A database is a collection of repository info that is organised in tables that are related to each other

Question 4

Eg. Of Popular Database Software

Answer 4

1. Microsoft Access
2. My SQL
3. Oracle Lite

Question 5

Define Database Management System (DBMS)

Answer 5

• A software package (eg. Microsoft Access) designed to define, manipulate, retrieve & manage data in a database
• A DBMS generally manipulates the data, the data format, field names, record structure & file structure

Question 6

Advantages of a DBMS

Answer 6

1. Reduction of Redundancy
   • redundancy is accumulating the same data items in more than one place
2. Sharing Data
   • In a manual database, data canNOT be shared among several users.
   • In computerised databases, many users can share the same data if they are connected via a network
3. Data Integrity
   • can be maintained by specific rules & restrictions regarding what kind of data may be entered into a database
4. Data Security
   • it is difficult to restrict persons from viewing a manual database but with a computerised database, this can be protected via the use of passwords

Question 7

Disadvantages of DBMS

Answer 7

1. Cost- this system is very EXPENSIVE to implement and maintain
2. Size- the complexity of a DBMS causes the software to be extremely LARGE, occupying many GB of DISC SPACE & requiring substantial amount of MEMORY to run it efficiently