Revoking privileges in MySQL - Step-by-Step Execution

Concept Flow - Revoking privileges

Start

↓

Identify user and privileges

↓

Execute REVOKE command

↓

Check if privileges exist

Yes No↓

Remove privileges

↓

Confirm success

↓

End

The flow shows starting with identifying the user and privileges, executing the REVOKE command, checking if privileges exist, removing them if yes, and confirming success.

Execution Sample

MySQL

REVOKE SELECT, INSERT ON mydb.* FROM 'user1'@'localhost';

This command removes SELECT and INSERT privileges on all tables in 'mydb' from user1 connecting from localhost.

Execution Table

Step	Action	Privileges Before	Privileges Revoked	Privileges After	Result
1	Identify user 'user1'@'localhost'	SELECT, INSERT, UPDATE	N/A	SELECT, INSERT, UPDATE	User found with privileges
2	Execute REVOKE SELECT, INSERT ON mydb.* FROM 'user1'@'localhost'	SELECT, INSERT, UPDATE	SELECT, INSERT	UPDATE	Privileges revoked successfully
3	Check remaining privileges	UPDATE	N/A	UPDATE	User retains UPDATE privilege
4	End	UPDATE	N/A	UPDATE	Revoking process complete

💡 Privileges SELECT and INSERT revoked; user retains UPDATE privilege; process ends.

Variable Tracker

Variable	Start	After Step 2	Final
Privileges	SELECT, INSERT, UPDATE	UPDATE	UPDATE

Key Moments - 2 Insights

Why do some privileges remain after the REVOKE command?

Only the specified privileges (SELECT, INSERT) are revoked; others like UPDATE remain unchanged as shown in execution_table step 2 and 3.

What happens if you try to revoke privileges the user does not have?

No change occurs; the command completes without error but no privileges are removed, similar to the 'No change' branch in the concept_flow.

Visual Quiz - 3 Questions

Look at the execution_table, what privileges does the user have after step 2?

A SELECT, INSERT, UPDATE

B UPDATE

C SELECT, INSERT

D No privileges

💡 Hint

Refer to the 'Privileges After' column in row for step 2.

At which step does the REVOKE command actually remove privileges?

A Step 2

B Step 1

C Step 3

D Step 4

💡 Hint

Look at the 'Privileges Revoked' column in the execution_table.

If the user had no INSERT privilege initially, what would happen at step 2?

A INSERT privilege would be revoked anyway

B An error would occur

C No change for INSERT privilege

D All privileges would be revoked

💡 Hint

See key_moments explanation about revoking privileges the user does not have.

Concept Snapshot

REVOKE privileges syntax:
REVOKE privilege_list ON database.table FROM 'user'@'host';
Only specified privileges are removed.
Privileges not listed remain unchanged.
No error if revoking non-existent privileges.
Use to restrict user access rights.

Full Transcript

This visual execution trace shows how the REVOKE command works in MySQL. First, the user and their current privileges are identified. Then the REVOKE command removes the specified privileges. The system checks which privileges remain after revocation. Only the privileges listed in the REVOKE command are removed; others stay. If you try to revoke privileges the user does not have, nothing changes and no error occurs. This process helps manage user access by removing specific rights.