Problem creating a view

Question

I need some help with a query that I need to use in order to create a view.
It's fairly complicated, at least for me.
Here is a short summary of the problem:
There is a table involved called salesperson.
This table has a four digit salespersonid, lastname, firstname, hiredate, and supervisor columns.
The supervisor column holds the four digit salespersonid of the supervisor of that particular sales person.
This column is null if that salesperson is the supervisor.
Now I need to generate a view that summarizes book sales by salesperson and shipping state.
7 columns are required.
Salespersonid
Sales person Name
State (based on shipstate)
Total number of orders
total amount of sales
Total profit
Last name of person's supervisor.
It is that last one that is giving me fits.
I don't know how to get the supervisor last name in the output.
Also, if the salesperson is the supervisor (i.e. supervisor column is null) I need to display (none) there. It can't be blank.
Here is what I have so far:
SELECT s.salespersonid AS ID, s.lastname || ', ' || s.firstname AS salesperson, shipstate,
       COUNT(DISTINCT order#) AS "TOTAL ORDERS", SUM(retail * quantity) AS "GROSS SALES",
       SUM((retail - cost) * quantity) AS "PROFIT"
FROM  salesperson s LEFT JOIN orders o ON s.salespersonid = o.salespersonid
LEFT JOIN orderitems oi ON o.order# = oi.order#
LEFT JOIN books b ON oi.isbn = b.isbn
GROUP BY s.salespersonid, s.lastname || ', ' || s.firstname, shipstateIt seems to me that I have to use a self join but my brain is cooked, and I can't seem to figure this out.
I have scripts here that would generate the tables and data I am using.
It's a small database. (If anyone is familiar with Oracle 10g SQL by Joan Casteel it is the JustLeeBooks database used throughout that book)
I don't really want to post these scripts here. It would make for quite a long post.
There are seven of them to get the data consistent with what I am using here.
If someone is willing to spend some time helping me, I could e-mail them the scripts.
They are the script that sets up the initial database and then 6 more scripts I have written to get to this point.
They kind of build on one another.
Send me a private message if you are willing to do that.
We could then bring the discussion back here if that is to your liking.
Any takers?
Maybe someone can help without those scripts?

Answer 1

Hi..
If i understood you need this query can help you..
SELECT s.salespersonid AS ID, s.lastname || ', ' || s.firstname AS salesperson, shipstate,
       COUNT(DISTINCT order#) AS "TOTAL ORDERS", SUM(retail * quantity) AS "GROSS SALES",
       SUM((retail - cost) * quantity) AS "PROFIT",
       nvl(sup.lastname || ', ' || sup.firstname,'none') AS supervisor
FROM  salesperson s LEFT JOIN orders o ON s.salespersonid = o.salespersonid
LEFT JOIN orderitems oi ON o.order# = oi.order#
LEFT JOIN books b ON oi.isbn = b.isbn
LEFT JOIN salesperson sup ON s.supervisorid = sup.salespersonid
GROUP BY s.salespersonid, s.lastname || ', ' || s.firstname, shipstate, nvl(sup.lastname || ', ' || sup.firstname,'none') Not Tested.
Tell me if there is that you need !!!