Create materialized view with stores name of manufacturer, count of all repairs of all cars of current manufacturer, count of all car rentals for current manufacturer.

If manufacturer doesn't have rentals or repairs this anyway should be included in report.

$3\mathrm{.}2$ Query#$2$

Using materialized view created in Query$1.$ Create query that extract all data from materialized view and adds category of manufacturer $($additional attribute$).$ If manufacturer maintenances are more than rentals then manufacturer is bad, in other case $$ good.