Components of DBMS

a) Data Definition Language (DDL): Data Definition Language (DDL). IT is use to define the structure of a Database. The database structure definition (Schema) typically includes the following: Defining all data element. Defining data element field and records. Defining the name, field length, and field type for each data type. Defining control for field that can have only selective values. Defining the logical relationship among various data element. Defining access control for security purpose.

b) Data Definition Language (DDL): Data Definition Language (DDL). In short every thing about the database structure is included in its schema. This description can be use by system analyst in defining new application. It is possible to generate complete description from its schema.

c) Database Administrator: Database Administrator Database system are typically installed and coordinated by an individual called database Administrator. He have the overall authority to establish and control data definition and Standard. he is responsible for determining relationship among data element and designing database security. He also train programmer to use database. A DATA DICTONARY is develop to store DDL and even it is automatically updated by DDL module.

d) Data Manipulation Language (DML): Data Manipulation Language (DML) Once the structure is defined the database is ready for entry and manipulation of data. Data Manipulation Language (DML) includes the command to enter and manipulate the Data, with these commands the user can Add new records, navigate through the existing records, view contents of various fields, modify the data, delete the existing record, sort the record in desired sequence.