SQL Server - Windowed Functions

So, I'm in need of some help with some homework.

Below is the schema of the parts of the database that I need to use.

I'm sure that there are some redundancies in it (I would appreciate any help with the setup as well). Anyways, here is the assignment:

The sales manager would now like you to create a report that ranks her products by both their total sales and total sales quantity (each will be its own column). Create a stored procedure that returns
the following columns but also with the two new rank columns added.

Product Name | Orders Count | Total Sales Value | Total Sales Quantity

The CEO would like to know the sales based on last month's sales. Please provide her with a query to rank the products by the number of orders in the last month. There should be NO SKIPPED NUMBERS.

Create a SELECT statement that generates a list of orders with customer id, order date, etc. ***Use the row number function to generate a unique id for each row that is sorted by order date DESC

Solution

Try it

CREATE PROCEDURE report_salesmanager 
AS 
  WITH cte_main AS 
  ( 
             SELECT     p.NAME, 
                        Isnull(Count(DISTINCT o.orderid), 0)  corderid, 
                        Sum(Isnull(o.ordertotal, 0))          sordertotal, 
                        Sum (Isnull(oi.orderitemquantity, 0)) sorderitemquantity 
             FROM       product p 
             LEFT JOIN  orderitem oi 
             INNER JOIN orders o 
             ON         o.orderid - oi.orderid 
             ON         p.productid = oi.productid 
             GROUP BY   p.NAME), cte_rank_value AS 
  ( 
           SELECT   NAME, 
                    Rank() OVER( ORDER BY sordertotal DESC) rk 
           FROM     cte_main), cte_rank_qtd AS 
  ( 
           SELECT   NAME, 
                    Rank() OVER( ORDER BY sorderitemquantity DESC) rk 
           FROM     cte_main) 
  SELECT     a.NAME [Product Name], 
             a.corderid, 
             [Orders Count] a.sordertotal [Total Sales Value], 
             b.rk [Rank Total Sales Value], 
             a.sorderitemquantity [Total Sales Quantity], 
             c.rk [Rank Total Sales Quantity] 
  FROM       cte_main a 
  INNER JOIN cte_rank_value b 
  ON         a.NAME = b.NAME 
  INNER JOIN cte_rank_qtd c 
  ON         a.NAME = c.NAME

GO

CREATE PROCEDURE report_ceo 
AS 
  DECLARE @somedateLastMonth DATE = Dateadd(-1,m,Getdate()) WITH cte_main AS 
  ( 
             SELECT     p.NAME, 
                        Isnull(Count(DISTINCT o.orderid), 0)  corderid, 
                        Sum(Isnull(o.ordertotal, 0))          sordertotal, 
                        Sum (Isnull(oi.orderitemquantity, 0)) sorderitemquantity 
             FROM       product p 
             INNER JOIN orderitem oi 
             INNER JOIN orders o 
             ON         o.orderid - oi.orderid 
             ON         p.productid = oi.productid 
             WHERE      Year(o.orderdate) * 100 + Month(o.orderdate) = Year(@somedateLastMonth) * 100 + Month(@somedateLastMonth)
             GROUP BY   p.NAME), 
    cte_rank_value AS 
  ( 
           SELECT   NAME, 
                    Rank() OVER( ORDER BY sordertotal DESC) rk 
           FROM     cte_main), 
    cte_rank_qtd AS 
  ( 
           SELECT   NAME, 
                    Rank() OVER( ORDER BY sorderitemquantity DESC) rk 
           FROM     cte_main) 
  SELECT     a.NAME [Product Name], 
             a.corderid, 
             [Orders Count] a.sordertotal [Total Sales Value], 
             b.rk [Rank Total Sales Value], 
             a.sorderitemquantity [Total Sales Quantity], 
             c.rk [Rank Total Sales Quantity] 
  FROM       cte_main a 
  INNER JOIN cte_rank_value b 
  ON         a.NAME = b.NAME 
  INNER JOIN cte_rank_qtd c 
  ON         a.NAME = c.NAME
go


SELECT     Row_number() OVER (ORDER BY o.orderdate DESC, o.ordertime DESC) rowNumber ,
           * 
FROM       product p 
INNER JOIN orderitem oi 
INNER JOIN orders o 
ON         o.orderid - oi.orderid 
ON         p.productid = oi.productid 
INNER JOIN cart c 
ON         c.orderid = o.orderid