Oracle Revoke Grant - SQL

Introduction

Oracle is a popular database management system used by many companies to store and manage their data. SQL (Structured Query Language) is used to communicate with the database and perform various operations on it.

One of the important operations in SQL is granting privileges to users. Granting privileges provides users with access to perform certain operations on the database objects. However, sometimes it may be necessary to revoke these privileges from users. This can be achieved using the 'REVOKE' command in SQL.

Revoke Grant Syntax

The syntax for revoking a grant in Oracle SQL is as follows:

REVOKE privilege_type
ON object_name
FROM user;

Where:

• privilege_type: specifies the privilege that is being revoked. Examples include SELECT, INSERT, UPDATE, DELETE, EXECUTE, etc.
• object_name: specifies the database object on which the privilege is granted, such as a table, view, sequence, or procedure.
• user: specifies the user from whom the privilege is being revoked.

Examples

Let's see some examples of how to use the Revoke command:

Example 1

Suppose we have granted the SELECT privilege on the 'employees' table to the user 'user1'. To revoke this privilege, we can use the following command:

REVOKE SELECT
ON employees
FROM user1;

Example 2

Suppose we have granted the EXECUTE privilege on the 'my_proc' procedure to the role 'manager'. To revoke this privilege from the role, we can use the following command:

REVOKE EXECUTE
ON my_proc
FROM manager;

Example 3

Suppose we have granted all privileges on the 'my_table' table to the user 'admin'. To revoke all privileges, we can use the following command:

REVOKE ALL
ON my_table
FROM admin;

Conclusion

In this article, we learned how to use the Revoke command in Oracle SQL to revoke privileges from users or roles. It is important to properly manage user privileges to ensure the security and integrity of the database.