Database Management Concepts


Syllabus requires you to:


Review of Database concepts (from AS unit 2):


Relational Database Management System (RDBMS)

"A database management system (DBMS) is a method for managing the interface between data that an organisation stores and the programs that it uses to access that data.

Typically, an organisation will store its data in a series of connected data files.

Users will not need access to the same data files.

A DBMS manages these different needs in an organised and efficient manner."

Alan Gardner: AS & A Level ICT through diagrams.

 

 


Advantage

Description

Examples

Single Centralised Store

Common data can be shared to all related tables within the organisation regardless of the software package you are using.

SIMS (Student Teachers Academic Records) can be shared in Assessment, Timetabling modules.

Data Redundancy is reduced if not got rid of.

Because there is only one copy of each attribute kept- duplication should be eliminated altogether in a well-designed RDBMS

Changes in personal details are changed in STAR only.

Data Independence

Each table can be administered without reference to other tables, although changes will take immediate effect within related information.

If a Department changes GCSE board this can be changed once in the Courses Table – as long as the Course ID remains the same?

Data Integrity.

Data should now be up to date, the same throughout, accurate and in general can be trusted.

Reports can easily be created with flexible layouts.

Easy to set up new relationships and new entities. New tables and reports can be set up as and when required.

Effort and Attainment grades can be entered centrally and shared wherever and whenever required.

Easier Security

All access to data is via a centralised system, a uniform system of security monitoring can be implemented

MIS is improved

Rather than concentrating on overcoming collection problems can now become creative in generating information.

Identify trends, exception reports, Model different scenarios.


Data Modelling


Relational Database Design

Table Design:

 

Entity Relationship Diagrams

Normalisation

Database Management

Data Dictionary

‘a database about the database’.

It will contain information such as:


Functions of a DBMS

Advantage and Disadvantages of a DBMS

 

Case study:


 

Check your knowledge:



 

Exercise: