Help! My Database Stopped Working

What do you do when MySQL stopped working? Here are my 2 cents on what you should do.

1. Check if the database is running. Check the MySQL process.
   
   ps -aux | grep mysql
   
   
2. Check the error logs. Where is the location of the error logs again? The default location would be at /usr/local/mysql/data/ and look for a file with .err at the end of it. Sample errors would be:
   
   
   • Database got restarted - check with your sys admin why it restarted.
   • Replication failed - do a show slave status and check the error then restart the replication.
   
   
3. Check the MySQL process list and see if there are any read / write locking happening.
   
   show processlist