thanx you very much, I will try both and check what will be better for me

I know that is strong but this table is mainly used for car not for user 

ok good query, but I need how many hours...

Ok, but with this you have sum of hour thath worker do on all cars....so he can work more then 24 per day....I need this

start work on car 1 - 8:30...

Thanx exactly this I need

I understand, that I can use select TOP 100 * ...

but this filter I need for all query on DB. And I would like found some way where I not...