Database Theory And Design

Question 1

Definition of database

Answer 1

Organized collection of related data

Question 2

What is a file based system

Answer 2

Collection of application programs that provide services for users, each defining and maintain its own data

Question 3

Advantages of file based

Answer 3

• end user has total control of data
  -applications can be optimized for particular use

Question 4

Disadvantages of file based

Answer 4

-Data duplication is common
- integrity may be compromised if files are not updated entirely
-Different file types between applications is common so conversions must happen
-High level of data dependency

Question 5

Advantages of databases

Answer 5

-Data redundancy can be controlled
-Data is shared between applications
-Improved data integrity
-Improved security
-Improved data standards(all data in same format)
-Improved security
-Economy of scale (cheaper to have one large database)
-Improved data accessibility
-Easier maintenance
-Backup and recovery services

Question 6

Disadvantages of databases

Answer 6

-Complexity
-Size
-Cost
-Performance
-Greater impact in the event of failure