Data management technology like everything else, has undergone evolution process to reach its present complexity and functionality.
Before the advancement in data management technology, organizations utilized Traditional File Processing system to organize and maintain their databases. However, this system has many limitations that we'll see through later.
After the data management technology improved, various firms had adopted the modern data management approach, which is the utilization of Database Management system. With much more stability, reliability and security the data warehouse provided, the traditional file processing system is being slowly phased out from the business organizations.
1) Traditional File Processing System
- Each user defines and implements the needed files for a specific application to run, meaning there will be multiple files created all containing some similar information. For example, the student ID of a UTAR student will be found in both the course registration files and also the UTAR portal administration files because the student ID is needed in both files.
- Were an early attempt to computerize the manual filing system.
- Is a collection of application programs that perform services for the end-users.
- Each program defines and manages its own data.
Disadvantages :
1) Separation and isolation of data
- When data is isolated in separate files, it is more difficult for us to access data that should be available. The application programmer is required to synchronize the processing of two or more files to ensure the correct data is extracted.
2) Duplication of data
- Means the same data were recorded and stored in different files.
- Independent data files create many duplicated data.
- When employing the decentralized traditional file processing system, the uncontrolled duplication of data will occur. Uncontrolled duplication of data is undesirable because:
i) Duplication is wasteful
ii) Duplication can lead to loss of data integrity
3) Data dependence
- Using traditional file processing system, the physical structure and storage of the data files and records are defined in the application program code.
- This characteristic is known as program-data dependence. Making changes to an existing structure are rather difficult and will lead to a modification of program.
- Such maintenance activities are time-consuming and subject to error.
4)Incompatible file formats
- The structures of the file are dependent on the application programming language. However file structure provided in one programming language such as direct file, indexed-sequential file which is available in COBOL programming, may be different from the structure generated by other programming language such as C.
- The direct incompatibility makes them difficult to process jointly.
5) Fixed queries / proliferation of application programs
- File-based systems are very dependent upon the application programmer. Any required queries or reports have to be written by the application programmer. Normally, a fixed format query or report can only be entertained and no facility for ad-hoc queries if offered.
- File-based systems also give tremendous pressure on data processing staff, with users' complaints on programs that are inadequate or inefficient in meeting their demands.
- Documentation may be limited and maintenance of the system is difficult.
- Provision for security, integrity and recovery capability is very limited.
2) Database Management System (DMS)
- A single repository of data (data warehouse) is maintained that is defined once and then accessed by many users, using different programs.
- Sharing of data is possible.
- Set of computer programs that governs the creation, maintenance, and the utilization of the database with computer as a platform of an organization and its end users.
- May use a variety of database models, such as the network model or relational model.
- In large systems, a DBMS allows users and other software to store and retrieve data in a structured way, by using concurrency control software.
- Provides facilities for recovering hardware and software failures, thus reduces the application development time considerably when compared to the file system approach and availability of up-to-date information of all the users.
- Also provides security to the data stored in the database system.
Advantages :
1) Control of data redundancy
- The database approach tries to eliminates the redundancy by integrating the files. Although the database approach does not eliminate redundancy entirely, it controls the amount of redundancy inherent in the database.
2) Data consistency
- By eliminating or controlling redundancy, the database approach reduces the risk of inconsistencies occurring. It ensures that all copies of the data are kept consistent.
3) More information from the same amount of data
- With the integration of the operated data in the database approach, it may be possible to derive additional information for the same data.
4) Sharing of data
- Database belongs to the entire organization and can be shared by all authorized users.
5) Improved data integrity
- Database integrity provides the validity and consistency of stored data. Integrity is usually expressed in terms of constraints, which are consistency rules that the database is not permitted to violate.
6) Improved security
- Database approach provides a protection of the data from the unauthorized users. It may take the term of user names and passwords to identify user type and their access right in the operation including retrieval, insertion, updating and deletion.
7) Enforcement of standards
- The integration of the database enforces the necessary standards including data formats, naming conventions, documentation standards, update procedures and access rules.
8) Economy of scale
- Cost savings can be obtained by combining all organization's operational data into one single database with applications to work on one source of data.
9) Balance of conflicting requirements
- By having a structural design in the database, the conflicts between users or departments can be resolved. Decisions will be based on the base use of resources for the organization as a whole rather that for an individual entity.
10) Improved data accessibility and responsiveness
- By having an integration in the database approach, data accessing can be crossed departmental boundaries. This feature provides more functionality and better services to the users.
11) Increased productivity
- The database approach provides all the low-level file-handling routines. The provision of these functions allows the programmer to concentrate more on the specific functionality required by the users. The fourth-generation environment provided by the database can simplify the database application development.
12) Improved maintenance
- Database approach provides a data independence. As a change of data structure in the database will be affect the application program, it simplifies database application maintenance.
13) Increased concurrency
- Database can manage concurrent data access effectively. It ensures that no interference between users that would not result any loss of information nor loss of integrity.
14) Improved backing and recovery services
- Modern database management system provides facilities to minimize the amount of processing that can be lost following a failure by using the transaction approach.
SQL Server Enterprise Manager
Example of Another Database Management SoftwareData Warehouse
- Subject-oriented data repository designed with enterprise-wide access in mind.
- In addition to data query and reporting, a data warehouse provides facility for getting quick, accurate, and often insightful information
- Is designed so that its users can recognize the information they want and access that information using simple tools.
- Integrates operational data from various sources into a single and consistent architecture that supports analysis and decision-making within the organization
- Operational (legacy) systems create, update and delete production data that "feed" the Data Warehouse.
Advantages :
1) More cost-effective decision making
- Integration of various operational data into a single source helps in lowering the cost in analysis and decision making.
2) Better enterprise intelligence
- All the data can be governed by tapping into a single source thus helping the identification of possible problems or business advantages.
3) Enhanced customer service
- Faster decision making and actions carried out ensures shorter time the customers will have to wait. Therefore improving customer services.
4) Allowing business reengineering
- The integration of data make it easier to redesign the business organization whether completely or partially.
5) Information system reengineering
- Information system can be redesigned easier due to the flexibility of data management offered by the data warehouse.
Data Warehouse Diagram
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