-- 01 ORACLE

-- WHERE:
Select c.companyname, o.orderdate, e.lastname
	From orders o, customers c, employees e
	Where o.customerid=c.customerid and
	o.employeeid=e.employeeid;



-- FROM:
Select companyname, orderdate, lastname
	From orders o
	Join customers c
	On o.customerid=c.customerid
	Join employees e
	On o.employeeid=e.employeeid;



-- 02 ORACLE

-- WHERE:
Select o.orderdate, q.quantity, p.productname
	From Orders o, Orderdetails q, products p
	Where o.orderid=q.orderid and q.productid=p.productid;


-- FROM:
Select orderdate, quantity, productname
	From orders o
	Join orderdetails q
	On o.orderid=q.orderid
	Join products p
	On q.productid=p.productid;



-- 03 ORACLE

-- WHERE:
Select p.productname, c.categoryname, sum(o.quantity) as "Total Quantity"
	From Products p, Categories c, Orderdetails O
	Where p.categoryid = c.categoryid and p.productid = o.productid
	Group By Productname, Categoryname
	Order By sum(quantity) desc;


-- FROM:
Select Productname, categoryname, sum(quantity) as "Total Quantity"
	From Products p
	Join Categories c
	On p.categoryid = c.categoryid
	Join Orderdetails o
	On p.productid = o.productid
	Group By Productname, categoryname
	Order By sum(quantity) desc;



-- 04 ORACLE

-- WHERE:
Select e.Lastname, t.TerritoryDescription, r.RegionDescription
	From Employees e, Territories t, Region r, Employeeterritories i
	Where t.regionid = r.regionid and i.territoryid = t.territoryid and e.employeeid = i.employeeid
	Order By Lastname;



-- FROM:
Select Lastname, TerritoryDescription, RegionDescription
	From Territories t
	Join Region r
	On t.regionid = r.regionid
	Join Employeeterritories i
	On i.territoryid = t.territoryid
	Join Employees e
	On e.employeeid = i.employeeid
	Order By Lastname;