Question

I have a query which I would like to tweak little bit to display different info.
Currently my query gets all the orders with products ranked by the one with most conversions at the top.
Here is the query:

   SELECT nopv.ProductVariantID, COUNT(nopv.ProductVariantID), p.ProductId, c.CategoryID, c.Name FROM Nop_OrderProductVariant nopv
INNER JOIN Nop_ProductVariant npv
ON nopv.ProductVariantID = npv.ProductVariantId
INNER JOIN Nop_Product p
ON npv.ProductID = p.ProductId
INNER JOIN Nop_Product_Category_Mapping npcm
ON p.ProductId = npcm.ProductID
INNER JOIN Nop_Category c 
ON npcm.CategoryID = c.CategoryID
GROUP BY nopv.ProductVariantID, p.ProductId, c.CategoryID, c.Name
HAVING COUNT(*) > 0
ORDER BY COUNT(nopv.ProductVariantID) DESC

What I have as a result is:

I want to be able to have each category only one time, for example “programmers & modules” category should only one record, containing the sum of all the productvariantIDs in that category. The first field can be avoided as well, because if there are multiple productvariants, the query will need to show just one. What I really need is the count of each category and the categoryID.
Thanks in advance, Laziale

Answer 1

I think the issue is your group by:

GROUP BY nopv.ProductVariantID, p.ProductId, c.CategoryID, c.Name

Try:

GROUP BY c.CategoryID, c.Name -- c.Name is here since you probably can't select it otherwise

Then make whatever changes you need to your SELECT so it will work.

So something like this:

SELECT COUNT(nopv.ProductVariantID), c.CategoryID, c.Name
FROM Nop_OrderProductVariant nopv
INNER JOIN Nop_ProductVariant npv
ON nopv.ProductVariantID = npv.ProductVariantId
INNER JOIN Nop_Product p
ON npv.ProductID = p.ProductId
INNER JOIN Nop_Product_Category_Mapping npcm
ON p.ProductId = npcm.ProductID
INNER JOIN Nop_Category c 
ON npcm.CategoryID = c.CategoryID
GROUP BY c.CategoryID, c.Name
HAVING COUNT(*) > 0
ORDER BY COUNT(nopv.ProductVariantID) DESC