Advantages of DBMS Over File System
In this Article is you will know about Advantages of DBMS Over File System
The Database Approach
In order to overcome the limitations of a file system, a new approach was required. Hence a database approach emerged. A database is a persistent collection of logically related data. The initial attempts were to provide a centralised collection of data. A database has a self-describing nature. It contains not only the data but also the complete definition of the database structure and constraints, which are stored in a system catalog.
A DBMS manages this data. It allows data sharing and integration of data of an organisation in a single database. DBMS controls access to this data and thus needs to provide features for database creation, data manipulation such as data value modification, data retrieval, data integrity and security etc. Let us describe some of the advantages of the database approach.
The database approach has many advantages. Let us discuss these in more detail.
Reduction of Redundancies
In a file processing system, each user group maintains its own files resulting in a considerable amount of redundancy of the stored data. This results in wastage of storage space but more importantly may result in data inconsistencies. Also, the same data has to be updated more than once resulting in duplication of effort. The files that represent the same data may become inconsistent as some may be updated whereas others may not be. Advantages of DBMS Over File System
In database approach data can be stored at a single place or with controlled redundancy under DBMS, which saves space and does not permit inconsistency.
A DBMS allows the sharing of database under its control by any number of application programs or users. A database belongs to the entire organisation and is shared by all authorised users (may not be the complete data, why?). This scheme can be best explained with the help of a logical diagram (Figure 2). New applications can be built and added to the current system and data not currently stored can be stored.
In the file-based system, the descriptions of data and logic for accessing the data are built into each application program making the program more dependent on data. A change in the structure of data may require alterations to programs. Database Management systems separates data descriptions from data. Hence it is not affected by changes. This is called Data Independence, where details of data are not exposed. DBMS provides an abstract view and hides details. For example, logically we can say that the interface or window to data provided by DBMS to a user may still be the same although the internal structure of the data may be changed.
Advantages of DBMS Over File System
Data Integrity refers to validity and consistency of data. Data Integrity means that the data should be accurate and consistent: This is done by providing some checks or constraints. These are consistency rules that the database is not permitted to violate. Constraints may apply to data items within a record or relationships between records. For example, the age of an employee can be between 18 and 70 years only.
While entering the data for the age of an employee, the database should check this. However, if Grades of any student are entered, the data can be erroneously entered as Grade C for Grade A. In this case DBMS will not be able to provide any check as both A and C are of the same data type and are valid values.
Efficient Data Access
DBMS utilises techniques to store and retrieve the data efficiently at least for unforeseen queries. A complex DBMS should be able to provide services to end users, where they can efficiently retrieve the data almost immediately.
Multiple User Interfaces
Since many users having varying levels of technical knowledge use a database, a DBMS should be able to provide a variety of interfaces. This includes —
- query language for casual users,
- Programming language interfaces for application programmers,
- forms and codes for parametric users,
- menu driven interfaces, and
- natural language interfaces for standalone users, these interfaces are still not
- available in standard form with commercial database.