Question

I have a table (Order_line_t) with the following format:

Order_ID    Product_ID    Quantity
--------    ----------    --------
1001        1             2
1001        2             2
1001        4             1
1002        3             5
1003        3             1
1004        6             2
1004        8             2
1005        4             4
1006        1             1
1006        5             2
1006        7             2
1007        1             3
1007        2             2
1008        3             2
1008        8             3
1009        4             2
1009        7             3
1010        8             10

My goal is to show the total quantity that has been ordered by descending popularity for each product like this: (I used my current query and clicked on Descending Filter for Column Total_Quantity to achieve this result)

Product_ID    Total_Quantity
----------    --------------
8             15
4             8
3             8
7             5
1             5
2             4
6             2
5             2

I have been trying to figure this out for 3 hours, and I don’t know where I my error is. My current SQL Query is this:

SELECT  Product_ID, SUM(Quantity) AS Total_Quantity
FROM Order_line_t
GROUP BY Product_ID

My Query result is this:

Product_ID    Total_Quantity
----------    --------------
1             5
2             4
3             8
4             8
5             2
6             2
7             5
8             15

Thanks in advance, I am just beginning to learn SQL. Please bear with me.

Answer 1

SELECT  Product_ID, SUM(Quantity) AS Total_Quantity
FROM Order_line_t
GROUP BY Product_ID
ORDER BY SUM(Quantity) DESC;

OR

SELECT Product_ID, Total_Quantity
FROM
(
    SELECT  Product_ID, SUM(Quantity) AS Total_Quantity
    FROM Order_line_t
    GROUP BY Product_ID
) SQ
ORDER BY Total_Quantity DESC;