Selecting ID's based on multiple subquery - sql

Question

This my my first post to Stack Overflow, I appreciate and will take in any positive criticism to better form any future questions.
Question:
I'm trying to create a Select query where to gather all orders which have only the top 8 items in them.
I'm working with MS-Access 2013.
My current Query, which doesn't work, looks like this.
SELECT OrderID
From DirectOrders
WHERE OrderID <> ANY
(
SELECT OrderID
FROM DirectOrders
WHERE SKU <> ANY
(
SELECT TOP 8 SKU
FROM DirectOrders
GROUP BY SKU
ORDER BY COUNT(SKU) DESC
)
)
The single table that is below.
OrderID Customer SKU Qty
177622 CustomerA 1001 20
177622 CustomerA 1002 2
177624 CustomerB 1001 200
177626 CustomerC 1003 50
177626 CustomerC 1004 150
177630 CustomerC 1005 1000
177632 CustomerA 1006 1
177632 CustomerA 1007 3
177632 CustomerA 1008 9
177632 CustomerA 1009 1
177632 CustomerA 1010 4
177632 CustomerA 1011 3
177634 CustomerC 1012 5
177634 CustomerC 1013 5
177640 CustomerD 1014 4
177642 CustomerA 1015 4
177642 CustomerA 1016 48
177642 CustomerA 1017 15
177644 CustomerB 1018 50
Here was the flow that I was trying to accomplish.
Select Top 8 SKU's by Count
Select All OrderID's that do not have one of those 8 SKU's
Select All OrderID's That are not part of the selected OrderID's in List 2.

Answer 1

I would do this with aggregation:
SELECT do.OrderID
FROM DirectOrders as do LEFT JOIN
(SELECT TOP 8 SKU
FROM DirectOrders
GROUP BY SKU
ORDER BY COUNT(SKU) DESC, SKU
) as s8
ON do.SKU = s8.SKU
GROUP BY do.OrderId
HAVING COUNT(*) = COUNT(s8.SKU);
Notes:
In MS Access, TOP is really TOP WITH TIES. To get exactly 8 values you need a tie breaker. This query uses SKU for that purpose.
The LEFT JOIN determines if there is a match between each item in an order and the top 8 items.
The HAVING clause is saying: The count of rows with items is the same as the count of rows that match one of the top 8. Hence, all are in the order.

Answer 2

I think you need something like this. However, you might get some strange results if you are using count SKU because apart from 1001 the count of the other SKUs is 1. So apart from 1001, all the other SKUs are in the top 8 based on the count(SKU)
SELECT * FROM DirectOrderswhere SKU in
(select top 8 SKU from DirectOrders group by SKU order by count(SKU) desc);

Answer 3

Access's TOP function does not break ties, so instead of reporting just the top 8, it will order the items per your order by and then report enough to cover the top value you put in, and all ties. For example, with your sample data, it will report the same 17 records if you do top 8 or just top 2, since all but one of your SKUs have only 1 order.
If you want to report only the top 8, you should add to the query to make the ordering unique. In this case, I would probably order by COUNT(SKU) DESC, COUNT(QTY) DESC, MAX(ORDERID) desc, SKU So that it prioritizes highest number of orders, highest quantity, and then makes a choice based on the latest OrderID with that sku, and if all else fails, order by the SKU itself. Only the SKU is guaranteed to be unique for each row, but just ordering by SKU might not give the best result if you are looking for the truly relevant "top 8".
SELECT OrderID
From DirectOrders
WHERE OrderID NOT IN
(
SELECT OrderID
FROM DirectOrders
WHERE SKU NOT IN
(
SELECT TOP 8 SKU
FROM DirectOrders
GROUP BY SKU
ORDER BY COUNT(SKU) DESC, SUM(QTY) DESC, MAX(ORDERID) DESC, SKU
)
)