Chapter 7

CHAPTER 7 :

STORING ORGANIZATIONAL INFORMATION

( DATABASES)

This chapter stated that information is stored in databases to 
maintain the information such as various types of objects (inventory), 
events (transaction), people (employees) and places (warehouse). 

DATABASES MODAL :

Hierarchical databases model 

Information organized into a tree-like structure.

Network databases model

a flexible way of representing objects and their relationship

Relational databases model

stores information in the form of logically related 2D tables

KEYS AND RELATIONSHIP :

Primary key

a fields that unique identifies a given entity in a table.

Foreign key

a primary key of one tables that appears an attribute in another table

and acts to provide a logical relationship among the two tables.

DATABASE ADVANTAGE :

INCREASED FLEXIBILITY
·         A well-designed database should :

INCREASED SCALABILITY AND PERFORMANCE
·          A database must scale meet increased demand, while maintaining 

acceptable performance levels

Scalability 

how well a system can adapt to increased demand.

 Performance

measure how quickly a system perform certain process or 

transaction.

INCREASED INFORMATION REDUNDANCY
·         Database reduce information redundancy

Redundancy

The duplication of information or storing the same information in

multiple places.

·         Inconsistency is one of the primary problem with redundant information

difficult to decide which is most current and most accurate.

INCREASED INFORMATION INTEGRITY (QUALITY)

·         Information integrity - measure the quality of information

·         Integrity constraint - rules that help ensure the quality of 

  information 

Relational integrity constraint

Rule that enforces basic and fundamental information based

constraints

Business-critical integrity constraint

Rule that enforce business rules vital to an organization's success

and often require more insight and knowledge than relational

integrity constraints.

INCREASED INFORMATION SECURITY
·         Information is an organizational asset and must be protected

·         Databases offer several security features including :

Password

provides authentication of the user.

Access level

determines who has access to the different types of information.

Access control

determines types of user access, such as read-only access.

DATABASES MANAGEMENT SYSTEM (DBMS) :

~ software through which users and application programs interact with a 

databases 

DATA-DRIVEN WEB SITES :

~ An interactive web site kept constantly updated and relevant to the

needs of its customer through the use of the database.

ADVANTAGE of Data-Driven websites :

Development

Allows the websites owner to make changes anytime without having

to rely on a developer or knowing HTML programming.

More efficient

With a data-driven solution, the system keeps track of the templates,

so users do not have to.

Improved stability

With a data-driven websites, there is peace of mind, knowing the

content is never lost.

INTEGRATING INFORMATION AMONG MULTIPLE

DATABASE :

·         Intergration - allows separate system to communicate directly

with each other

forward integration

takes information entered into a given system and sends it automatically

to all downstream system and processes.

Backward integrating

takes information entered into a given system and sends it automatically

to all upstream system and processes. 

·    Building a central repository specifically for integrated information

- Without integrating, an organizational will spend considerable time entering the same 

info in multiple system and suffer from the low quality and inconsistency 

typically embedded redundant info.