MySQL Quick Hacks & problem solving

Few day to day MySQL working, administration, hacking and problem solving tips.

1. ERROR 1 (HY000): Can't create/write to file '/tmp/#sql****.MYI' (Errcode: 13) 
1. Solution : This is basically due to messed up /tmp permissions
1. chown root:root /tmp
2. chmod 1777 /tmp
3. /etc/init.d/mysqld restart