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PRESENTED BY S.HAYAT 1

Traditional File Approach (TFA)

Traditional or simple file processing system is the first

computer based method to handles business applications.

When there were no databases, computer- based data

processing was first available.

Gradually computer were introduced into the business

world, to be useful for business applications.

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Traditional File Approach (TFA) (CONT)

Computer must be able to store, retrieve, and manipulatedata, so computer-based processing system were

developed for this purpose.

Although these systems have developed gradually, theirbasic structures and purpose have changed little over

several decades.

As business applications become more complex, it becomeevident that T.F.Processing system had number of

shortcomings and limitations.

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As result, these systems have replaced by databaseprocessing systems, in most critical business

application today.

Some familiarities with a file processing system are

i) :- File processing system are still widely used today

especially backing up database system.

ii):- Understanding the problems and limitations

inherent in file processing system can help us avoiding

these some problems when designing database.

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Let we study the following example (furniture makingcompany) for traditional file processing.

Pine Valley Furniture Company

-Make different type of furniture

-Distributor to national wide.

-Company using traditional file processing system

-Company have three departments (Order

department, Accounting department, Payroll department)

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Each department having own information system (Filesystem) which are specially designed for related files of

each department.

The following Fig shows the companys departments andtheir file system.which they are using. (next page)

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Figure. Three file processing systems at Pine Valley Furniture

Duplicate

Data

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This approach to information system design focused on thedata processing needs of individual departments instead of

evaluating the overall information needs of the

organization.

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Disadvantages of File Processing System

Program-Data Dependence All programs maintain metadata for each file they use

Data Redundancy (Duplication of data)

Different systems/programs have separate copies of the

same data Limited Data Sharing

No centralized control of data

Lengthy Development Times

Programmers must design their own file formats

Excessive Program Maintenance

80% of of information systems budget

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Advantages of File Processing System

Traditional file processing system is less complex system

One application can fail without effecting the others.

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Database Approach

--The database approach emphasizes the integration andsharing of data throughout the organization (or at least

across major segments of the organization).

--The Database Approach Central repository of shared data

Data is managed by a controlling agent

Stored in a standardized, convenient form

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Database Approach (cont)

Database approach at pine valley furniture company

--Pine valley furniturecompanys first step in converting to a

database approach was to develop a list of the high level

entities that support the business activities of theorganization.

--Some of the high-level entities identified at pine valley

furniture are the followingCUSTOMER, PRODUCT, CUSTOMER ORDER,

EMPLOYEE and DEPARTMENT.

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Database Approach (Cont)

-- After these entities were identified and defined, thecompany proceeded to develop anEnterprise Data Model.

Enterprise Data Model:- A graphical model that shows the

high-level entities for the organization and therelationships among those entities

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Figure 3 Segment from enterprise data model(Pine Valley Furniture Company)

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The entities shown in above segment model are the

following;

CUSTOMER: People and organization that buy or maypotentially buy products from pine valley furniture.

ORDER: the purchase of one or more products by customer.

PRODUCT: The items pine valley furniture makes and sells.

ORDER LINE: Details about each product sold onparticular

Customer order (such as quantity and price).

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Database Approach (Cont)Figure 3

Segment from enterprise data model

One customer may place many

orders, but each order is placed

by a single customer

One-to-many relationship

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Database Approach (Cont)Figure 3


One order has many order lines;

each order line is associated with a

single order


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Database Approach (cont)Figure 3

One product can be in many order

lines, each order line refers to asingle product



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Figure 3

Therefore, one order involves many

products and one product is involvedin many orders

Many-to-many relationship


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Some Charactistics of the Enterprise Data Model.

3. It is a model of the organization that provides valuable

information about how the organization functions as

well as important constraints.

5. The enterprise data model stresses the integration of data

and process by focusing on entities, relationships and

business rules.

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Relational Database: A database that represent data as acollection of tables in which all data relationships are

represented by common values in related tables.

The company decided to implement modern relationaldatabase management system that views all data in form of

tables.

The following fig shows tables represent four entities

shown in the enterprise data model.

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Figure ; Order, Order_Line, Customer, and Product tablesRelationships established in special

columns that provide links between

tables

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Each column of table represent an attribute (or

characteristics) of an entity.

Each row of a table represent an instance (or occurrence)

of the entity.

An important property of a relational model is that itrepresents relationships between entities by values stored

in the columns of the corresponding tables.

For example: Notice that Customer_ID is an attribute ofboth the customer table and the order table, as result we

can easily link an order to its associated customer.

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COMPARATVE STUDY B/W TFA & DBMS

TFA

The programs and data areinter-dependent..

Data may be duplicated indifferent files that causedata redundancy.

The data in different filesmay be different that

creates inconsistency The data is distributed in

many files and can't beshared

Database Approach

The programs and data are

independent of each other.

Data is not duplicated andappear only one.

The data appear only once

so it is always consistent.

The data is stored at oneplace and can be share

easily

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COMPARATVE STUDY B/W TFA & DBMS

It is difficult to apply dataintegrity checks on files

It provides poor securityas the data is widely

spread It is difficult to maintain

as it provides lesscontrolling facilities

It is less complex system One application can fail

without effecting theothers

This approach providesmany constraints forintegrity.

It provides many

procedures to maintaindata security.

It provides many facilitiesto the programs easily

It is very complex system Problem in one

application will effect thewhole system.

Documents

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