Database Languages : An Overview

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Database Languages

Database Languages are require because just like human being database management system also need communication languages for proper communication with database. These Database Languages are mainly used to create and maintain database. Along with this database languages are used to read data, store and update information in database. Also known as dbms languages.

dbms languages

Languages in DBMS

In database management system there are following types of dbms languages are used.

Data Definition Language(DDL)

Data Definition Language or DDL used to define the database schema. In database, it is used to create tables, constraints, indexes ,schema etc.  The operations that  can be performed on database using DDL are as follows

CREATE : It is used to create the database.

ALTER:  It is used to alter the structure of database .

DROP : It is used to  drop objects from database  tables.

TRUNCATE: It is used to delete tables in a database.

RENAME: It is used to rename database instances

COMMENT: It is used to Comment

All of the above queries or commands  either define or update the database therefore they all come under Data Definition language

Data Manipulation Language (DML)

DML is used to access and manipulate data in a database. The operations on database which comes under DML are 

SELECT: It is used to read records from table

INSERT: It is used to insert record(s) into the table

UPDATE: It is used to update the data in table

Delete: It is used to delete all the records from the table

 Data Control language (DCL)

The Data Control Language (DCL) is used for controlling the  privileges in Database. In the database, user need privileges to perform any operation  such as for creating tables, sequences or views.

GRANT: It is used to grant access to user

REVOKE: It is used to revoke access from user

Transaction Control Language(TCL)

Transaction Control Language (TCL) is used to manage the transactions of a database. These commands are used to manage the changes made by DML commands. The TCL commands are :

COMMIT – It is used to persist the changes made by DML commands

ROLL BACK – It is used to rollback the changes made to the database.
 
 

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