1. Check the error log for the MySQL 146 error:

$ tail -f /var/log/mysql/error.log

2. Check the MySQL configuration file for any misconfigurations:

$ cat /etc/mysql/my.cnf

3. Check the MySQL process list for any suspicious activity:

$ mysqladmin -u root -p processlist

4. Check the MySQL user table for any suspicious users:

$ mysql -u root -p -e "SELECT * FROM mysql.user;"

5. Check the MySQL privileges table for any suspicious privileges:

$ mysql -u root -p -e "SELECT * FROM mysql.user_privileges;"

6. Check the MySQL database for any suspicious tables:

$ mysql -u root -p -e "SHOW TABLES;"

7. Check the MySQL database for any suspicious data:

$ mysql -u root -p -e "SELECT * FROM [table_name];"

8. Use an automated database observability tool to monitor and fix the MySQL 146 in question. Automated database observability tools can provide real-time insights into the performance and health of your database, allowing you to quickly identify and fix any issues that may arise. Additionally, these tools can provide detailed metrics and logs that can be used to troubleshoot and diagnose any issues that may arise.