--1
Select C.CustomerID, CompanyName, Count(*)
from Orders O inner join Customers C on O.CustomerID = C.CustomerID and year(orderDate) = 1997
group by C.CustomerID, CompanyName

--2
Select P.ProductID, ProductName, Round(sum(Quantity*O.UnitPrice*(1 - Discount)), 0) as Bablo
from [Order Details] O inner join Products P on P.ProductID=O.ProductID
group by P.ProductID, ProductName
order by P.ProductID, ProductName

--4
Select top(3) CategoryName, P.CategoryID, Count(*) as Kol
from Products P inner join Categories C on (C.CategoryID = P.CategoryID and UnitPrice > 10)
group by P.CategoryID, CategoryName


--5
Select E.EmployeeID, LastName, FirstName, ShipCity, Count(*)
from Employees E inner join Orders O on O.EmployeeID = E.EmployeeID and ShipCity = ('Paris')
group by E.EmployeeID, ShipCity , LastName, FirstName