Database Management System
The DBMS is used for large and medium-sized organizations having different types of files for different purposes.
Objectives of DBMS
Different programs and people must be able to use the same data at the same time.
- Data and Database management system must be readily accessible to every user.
- It means centralization of information. In standard file system data is stored in many files at different locations it is difficult to access data from isolated files in database information is logically centralized. It means data is stored on the various computer, but it reasonably appears as a single file.
3. Data integrity
- Data integrity is related to the quality of data when a database contains any error it losses its integrity.
- Data integrity is related to security and protection. Security means to protect the data from unauthorized persons while integrity is associated with the quality of data.
- Data integrity is expressed in terms of integrity constraints. These are the rules designed to keep the data accurate and consistent.
Features of DBMS
1. Data Dictionary
- DBMS uses a file to store the data definition, or description of the structure of the database is called data dictiona6, i.e. data about a database.
2. Application Generator
- Application generator is a part of DBMS. It consists of tools that are used to create a complete database management application. A database application is a collection of queries, forms, and reports that are used to input and output data and perform various data manipulation operations.
3. Form Generator
- Form generator is used to create data input screens. The form generator enables developers to build forms by dragging and dropping form components such as text boxes, radio buttons, checkboxes, dropdown menus, etc.
4. Query Language
- SQL is a language used to insert, update, retrieve and delete any data item from the database.
- This language is also used to grant access rights to the database.
- This is a standard language used with all relational databases.
- The instruction of this language is English like and easily understandable.
5. Report Generator
- A program used to create a report in the form of hard/soft copy.
- The user can specify the report format.
- This format is very much flexible.
- A user can give headings and customize messages on this report.
- DBMS utilities are the software programs used to maintain the database by manipulating the data, records, and files. o Some programs are also used for backup and recovery procedures of the databases.
7. Access Security
- This facility is used to secure the data from unauthorized access.
- This feature makes the data secure and private.
- Access maintains the data security right like a password.
8. Backup and Recovery
- When data is stored in a database, there are chances of being lost or destroyed by natural disasters or by some human mistakes.
- And in the case of corruption of data or failure of system database can be reinstated with backup copy called recovery.