Foxpro Select Most Recent Order for Each Customer - visual-foxpro

Question

In a foxpro table, I have 4 fields: ordernum, orderdate, ordertotal, custpk.
What is the foxpro select statement to return all of those fields from the most recent order for each custpk?

Answer 1

Your table structure and what you want is not very clear. How do you define the "most recent order" for a given customer? Let's assume orderNum is primary key in that table and you decide "most recent order" for a given customer by the row having highest orderNum per customer. Then it is easy and a single VFP select command is sufficient (actually there are many SQL select variations that would return you the result you need. Below is one of those that would be most efficient):
select * from myTable ;
where orderNum in ;
(select max(orderNum) from myTable group by custPK)
BTW, VFP's SQL is close to ANSI-SQL 92.

Answer 2

I need a foxpro command, not SQL database
Let's start by saying that you will not get what you want with a single Foxpro command line.
Instead the most expedient manner to get this in Foxpro is to use Foxpro's SQL Query commands run on a FP/VFP Data Table and get the resultant data into a data table/cursor.
SELECT CustPk, OrderNum, OrderDate, OrderTotal FROM MyDataTable ORDER BY CustPk, OrderDate Desc INTO CURSOR OrderedData READWRITE
* --- Now ordered data is in memory cursor, use it however you need ---
* --- Each Customer's Most Recent Order will be first record ---
SELECT OrderedData
* --- You might just want to BROWSE the results to understand how the data appears ---
* --- Or you can do anything else with the data ---
< do whatever >
There are ways to get ONLY the most recent order per customer, but start here and see if that gets you what you need.
BTW: you might want to spend some time looking over the Free, On-line VFP tutorial videos at:
Free Visual Foxpro Videos
Good Luck

Answer 3

I would like to find how to do it with just the sql query command
Well I did it with just a SQL Query command, but you had to follow up with some other code.
EDIT: Oops: I forgot that Custpk is integer.
I am modifying the SQL Query syntax to take that into account.
Although it is still not a ONE LINE method, another way might be:
* --- Get reference records of only customer's last order date ---
SELECT STR(CustPk) AS cCustPk, MAX(OrderDate) AS LstOrdrDt FROM MyDataTable GROUP BY CustPk INTO CURSOR LstOrds READWRITE
* --- Now use that to get the complete last order for each customer ---
SELECT * FROM MyDataTable WHERE (STR(CustPk) + DTOS(OrderDate)) IN (SELECT cCustPk + DTOS(LstOrdrDt) AS KeyExp FROM LstOrds) INTO CURSOR OnlyLstOrds READWRITE
* --- Now you have ONLY the last orders ---
SELECT OnlyLstOrds
< do whatever >
NOTE the above code is off-the-cuff and not tested, so there might be a typo in it which you can fix.
Also note that one of the Free, On-line VFP Tutorial Videos at that site is named: FoxPro and the SQL Language
Good Luck