Name: usman aliyu
Database Systems Versus File System
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| 2.5.3 Database Systems Versus File System
The file system is supported by the operating system. The system is responsible for the storage of information in various files and also needs some application programs to extract and add information to these files. Before DBMS came along, many organizations store their information in the file system, even though keeping information there has some drawback. These are:- Data redundancy and inconsistency. Difficult in accessing data. Data isolation. Integrity problems. Atomicity problems. Security process. Data redundancy and consistency. There is data redundancy and consistency since different programs create different files and application programs resulting to files having different format and the use of different programming language. Apart from that, same information may be duplicate in so many places (Files) e.g. the address and telephone number may appear in a file that consists of grades or file that consists of courses. This redundancy may lead to higher storage and also data inconsistency (when various copies of the same data fail to agree). Difficulty in accessing data. File processing environments do not allow needed data to be retrieved in a convenient and effective manner. Let’s say for example a staff of KUK wants to find out the names of student from katsina Local Government. The staff may have to ask the faculty of sciences to generate such list. The problem is that there is no capable program for such request and the designers do not anticipate such request. The only program that exists is one that generates the list of all students of KUK. As such, the staff may choose from either assessing all the lists to find out the desired information or ask the system designers to write another application program. And suppose that after some days, the staff needs to trim such list to obtain students above 20 years he has to take the above options which are not satisfactory. 3. Data Isolation Since data is scattered in different files and each has its own format, writing programs to retrieve such data is very difficult. 4. Integrity Problems Information stored in a database system must meet some constraints which the designers must meet by adding codes in the application programs but when new programs to enforce them. With the file processing approach, it becomes difficult to enforce or to change those constraints. 5. Atomicity problems A computer like any other devices is subjected to failure. When such failure occurs, data should be restored to its initial state that existed before the failure. It is very difficult to ensure atomicity in a file system. 6. Security Problems Database systems are more secured than file systems because they prevent unauthorized usages i.e. not every user of the database system can have access to the data. These problems and others led to the development of DBMS. Download 0.97 Mb. Share with your friends:
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