Some useful database queries:
login to mysql database:
$ mysql $database_name -u $user_name -h $host_name -p
Take a dump by locking transactions
$ mysqldump -l -F $database_name -u $user_name -h $host_name -p > file.sql
*need lock table and read privilege from the host you trying
Take backup of only some tables
$ mysqldump -l -F $database_name -u $user_name -h $host_name --tables $tables_name -p > file.sql
Take backup of only database structure , without data
$ mysqldump -l -F -d $database_name> -u $username -h $hostname -p > file.sql
List the permissions assigned for a user
login to mysql:
> show grants for 'user'@'hostname';