Error
Error Code:
3724
MySQL Error 3724: Cannot Set Option
Description
This error indicates that MySQL was unable to set a specified configuration option or system variable. It typically occurs when the option is read-only, the user lacks sufficient privileges, or the option is being set in an incorrect scope.
Error Message
This option cannot be set %s.
Known Causes
3 known causesInsufficient User Privileges
The MySQL user attempting to modify the option does not possess the necessary `SUPER` or other specific privileges required for the operation.
Read-Only System Variable
The specific system variable or option you are trying to set is designated as read-only and cannot be changed after the MySQL server has started.
Incorrect Option Scope
The option is being set at the wrong scope, such as attempting to set a global-only variable as a session variable, or a session-only variable globally.
Solutions
3 solutions available1. Re-evaluate Option Usage in SET Statement easy
Identify and remove or correctly use the option causing the 'Cannot Set Option' error.
1
Examine the `SET` statement that produced the error.
SHOW VARIABLES LIKE '%<option_name>%';
-- Or examine your application code/script where the SET statement is located.2
Identify the specific option (`%s` in the error message) that is causing the problem. Common culprits include options that can only be set at server startup, or those with incorrect syntax.
3
If the option is intended to be set at runtime, ensure it's a valid session or global variable. Refer to the MySQL documentation for a list of settable variables and their scope.
SHOW VARIABLES WHERE Variable_name = '<option_name>';
SHOW GLOBAL VARIABLES WHERE Variable_name = '<option_name>';
SHOW SESSION VARIABLES WHERE Variable_name = '<option_name>';4
If the option is a server-level configuration parameter (e.g., `innodb_buffer_pool_size`), it cannot be set using `SET` during runtime. Modify the `my.cnf` or `my.ini` configuration file and restart the MySQL server.
5
Correct any typos or syntax errors in the `SET` statement.
SET GLOBAL <valid_option> = <value>; -- Example of a valid global setting
SET SESSION <valid_option> = <value>; -- Example of a valid session setting2. Adjust Scope of the SET Option easy
Use GLOBAL or SESSION keywords appropriately when setting variables.
1
Determine if the option you are trying to set is intended for the current session or for all subsequent connections (global).
2
If the option is meant to affect only the current connection, prefix it with `SESSION`.
SET SESSION <option_name> = <value>;3
If the option is meant to affect all new connections and the current session (and is allowed to be set globally), prefix it with `GLOBAL`.
SET GLOBAL <option_name> = <value>;4
If you receive the error 'This option cannot be set %s' when trying to use `SET GLOBAL`, it means the option is not designed to be changed dynamically or requires a server restart.
3. Modify MySQL Configuration File for Server-Wide Settings medium
For options that cannot be set at runtime, update the configuration file and restart the server.
1
Identify the MySQL configuration file. This is typically `my.cnf` on Linux/macOS or `my.ini` on Windows.
2
Locate the file. Common locations include `/etc/mysql/my.cnf`, `/etc/my.cnf`, or within the MySQL installation directory.
find / -name my.cnf 2>/dev/null
find / -name my.ini 2>/dev/null3
Open the configuration file with a text editor (e.g., `nano`, `vim`, `notepad`).
sudo nano /etc/mysql/my.cnf4
Find the relevant section (e.g., `[mysqld]`) and add or modify the option with its desired value. For example, to change `innodb_buffer_pool_size`:
[mysqld]
innodb_buffer_pool_size = 256M5
Save the changes to the configuration file.
6
Restart the MySQL server for the changes to take effect.
sudo systemctl restart mysql
-- Or for older systems:
sudo service mysql restart