MySQL non-default DB cleanup

Show me my non-default databases

for d in $(mysql -u root -e "show databases" | \
    grep -v 'Database\|mysql\|performance_schema\|information_schema'); \
do echo $d; done

Clean non-default databases

for d in $(mysql -u root -e "show databases" | \
    grep -v 'Database\|mysql\|performance_schema\|information_schema'); \
do echo $d; mysql -u root -e "drop database $d;"; done