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DCL (Data Control Language)

Data Control Language (DCL) is a subset of SQL used to control access to data within a database. DCL commands, such as GRANT and REVOKE, authorize or revoke privileges from users or roles. These commands specify what actions users or roles can perform on specific database objects, such as tables or views. DCL is essential for ensuring data security and enforcing access control policies in a database environment.

 

GRANT: DCL commands are used to control access to data within a database.

GRANT SELECT, INSERT, UPDATE ON employees TO user1;

In this example: We're granting specific privileges (SELECT, INSERT, UPDATE) on the 'employees' table to the user 'user1'. This allows 'user1' to perform these operations on the 'employees' table.

 

REVOKE: REVOKE is a Data Control Language (DCL) command used to revoke previously granted privileges from users or roles in a database.

REVOKE INSERT, UPDATE ON employees FROM user1;

In this example: We're revoking specific privileges (INSERT, UPDATE) on the 'employees' table from the user 'user1', thereby removing their ability to perform these operations on the table.

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