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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 manipulate data, so computer-based processing system were developed for this purpose. • Although these systems have developed gradually, their basic structures and purpose have changed little over several decades. • As business applications become more complex, it become evident that T.F.Processing system had number of shortcomings and limitations. PRESENTED BY S.HAYAT

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Traditional File Approach (TFA) (CONT) •

As result, these systems have replaced by database processing systems, in most critical business application today.

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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. PRESENTED BY S.HAYAT

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Traditional File Approach (TFA) (CONT) • Let we study the following example (furniture making company) 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) PRESENTED BY S.HAYAT

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Traditional File Approach (TFA) (CONT) • Each department having own information system (File system) which are specially designed for related files of each department. • The following Fig shows the company’s departments and their file system.which they are using. (next page)

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Traditional File Approach (TFA) (CONT) Figure. Three file processing systems at Pine Valley Furniture

Duplicate Data

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Traditional File Approach (TFA) (CONT) • This approach to information system design focused on the data 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 PRESENTED BY S.HAYAT

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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 and sharing 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 furniture company’s first step in converting to a database approach was to develop a list of the high level entities that support the business activities of the organization. --Some of the high-level entities identified at pine valley furniture are the following CUSTOMER, PRODUCT, CUSTOMER ORDER, EMPLOYEE and DEPARTMENT. PRESENTED BY S.HAYAT

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Database Approach (Cont) -- After these entities were identified and defined, the company proceeded to develop an Enterprise Data Model. Enterprise Data Model:- “A graphical model that shows the high-level entities for the organization and the relationships among those entities”

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Database Approach (Cont) Figure 3

Segment from enterprise data model (Pine Valley Furniture Company)

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Database Approach (Cont) The entities shown in above segment model are the following; CUSTOMER: People and organization that buy or may potentially 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 on particular Customer order (such as quantity and price). PRESENTED BY S.HAYAT

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Figure 3

Database Approach (Cont) 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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Figure 3

Database Approach (Cont) Segment from enterprise data model

One order has many order lines; each order line is associated with a single order  One-to-many relationship

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Figure 3

Database Approach (cont) Segment from enterprise data model

One product can be in many order lines, each order line refers to a single product  One-to-many relationship

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Database Approach (Cont) Figure 3

Segment from enterprise data model

Therefore, one order involves many products and one product is involved in many orders  Many-to-many relationship

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Database Approach (Cont) •

Some Charactistics of the Enterprise Data Model.

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It is a model of the organization that provides valuable information about how the organization functions as well as important constraints.

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The enterprise data model stresses the integration of data and process by focusing on entities, relationships and business rules.

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Database Approach (Cont) • Relational Database: A database that represent data as a collection of tables in which all data relationships are represented by common values in related tables. • The company decided to implement modern relational database 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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Database Approach (Cont) Figure ; Order, Order_Line, Customer, and Product tables

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Relationships established in special columns that provide links between tables

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Database Approach (Cont) • 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 it represents relationships between entities by values stored in the columns of the corresponding tables. • For example: Notice that Customer_ID is an attribute of both the customer table and the order table, as result we can easily link an order to its associated customer. PRESENTED BY S.HAYAT

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COMPARATVE STUDY B/W TFA & DBMS • TFA • The programs and data are inter-dependent.. • Data may be duplicated in different files that cause data redundancy. • The data in different files may be different that creates inconsistency • The data is distributed in many files and can't be shared

• Database Approach • The programs and data are independent of each other. • Data is not duplicated and appear only one. • The data appear only once so it is always consistent. • The data is stored at one place and can be share easily

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COMPARATVE STUDY B/W TFA & DBMS • It is difficult to apply data integrity checks on files • It provides poor security as the data is widely spread • It is difficult to maintain as it provides less controlling facilities • It is less complex system • One application can fail without effecting the others

• This approach provides many constraints for integrity. • It provides many procedures to maintain data security. • It provides many facilities to the programs easily • It is very complex system • Problem in one application will effect the whole system.

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