I have this script, I am using it to setup CRON job to execute this script, so it can check if MySQL service is running; if not then it restart the MySQL service:

#!/bin/bash
service mysql status| grep 'mysql start/running' > /dev/null 2>&1
if [ $? != 0 ]
then
    sudo service mysql restart
fi

I have setup cron job as.

sudo crontab -e

and then added,

*/1 * * * * /home/ubuntu/mysql-check.sh

Problem is that it restart MySQL on every cron job execution.. even if server is running it restart the MySQL service what is correction in the script to do that.