Categories of Sql Commands

Introduction

SQL is a standard language for relation database management system (RDBMS), which used to communicate with a database. This communication made by the different commands. These commands are different in kind. In the given below figure show the basic categories of SQL commands.

Explain

• DDL ( Data Definition Language )
  
  In this category, commands are used to create and modify database objects in the database. Such as create table, drop table , change table name and fields.
   
• DML ( Data Manipulation Language )
  
  In this category, commands are used to manipulate data. Such as select, update, insert, modify and delete data in the database.
   
• DCL ( Data Control Language )
  
  In this category, commands are used to authentication and authorization permission. Such as create user role, permission and referential integrity.
   
• TCL (  Transactional Control Language )
  
  In this category, commands are used to manage different logical transactions in the database. Such as commit and rollback  statement.