In SQL, the REVOKE statement is used to revoke privileges from a table. The syntax for revoking privileges from a table is as follows:
REVOKE privilege_type ON table_name FROM user_or_role;
Let’s break down the syntax:
privilege_type: Specifies the type of privilege to be revoked, such as SELECT, INSERT, UPDATE, DELETE, etc.table_name: Specifies the name of the table from which the privileges should be revoked.user_or_role: Specifies the user or role from which the privileges should be revoked.
For example, let’s say we want to revoke the SELECT privilege from the table named employees for a database user named john:
REVOKE SELECT ON employees FROM john;
Similarly, you can revoke multiple privileges at once using a comma-separated list. For example, to revoke both SELECT and INSERT privileges from the employees table for a role named manager:
REVOKE SELECT, INSERT ON employees FROM manager;
Remember, only users with the necessary permissions (usually database administrators) can revoke privileges from a table.
Revoking privileges is an essential step in controlling data access and maintaining the security of your SQL database. By carefully managing privileges, you can ensure that only authorized users have appropriate access to the data they need.