SQL consists of many types of statements which are classified in five types of sub-languages-

• Data Definition Language (DDL): to create and modify the structure of the database. All the commands of DDL are auto-committed that means it permanently save all the changes in the database.

DDL Commands:

               CREATE

               ALTER

               DROP

         TRUNCATE

• Data Manipulation Language (DML): DML commands are used to modify the database. It is responsible for all form of CHANGES in the database. The command of DML is not auto-committed that means it can’t permanently save all the changes in the database. They can be rollback.

DML Commands:

               INSERT

               UPDATE

               DELETE

• Data Control Language (DCL): DCL commands are used to GRANT and TAKE BACK authority from any database user.

DCL Commands:

               GRANT

               REVOKE

• Transaction Control Language (TCL): TCL commands can only use with DML commands like

INSERT, DELETE and UPDATE only.

TCL Commands:

               COMMIT

               ROLLBACK

               SAVEPOINT

• Data Query Language (DQL): DQL is used to fetch the data from the database.

DQL Command:

SELECT