Question

I am trying to use the following function that counts the number of orders by hour:

SELECT
    COUNT(id) total,
    DATENAME(HOUR, purchased_on) label,
    site
FROM dhs.dbo.orders
WHERE purchased_on >= '01/16/2013'
GROUP BY DATENAME(HOUR, purchased_on), site
ORDER BY label DESC

I am getting the following results even though I am using and ORDER BY clause that should put them in order from the highest label to the lowest:

total   label   site
2         9     AMAZON
1         9     DHS
2         8     AMAZON
1         7     AMAZON
1         6     AMAZON
1         4     AMAZON
1         12    AMAZON
3         11    AMAZON
1         10    AMAZON
1         10    DHS  

Why doesn’t the order by work?

Answer 1

DATENAME returns a VARCHAR.

Replace it with DATEPART:

SELECT  COUNT(id) total,
        DATEPART(HOUR, purchased_on) label,
        site
FROM    dhs.dbo.orders
WHERE   purchased_on >= '01/16/2013'
GROUP BY
        DATEPART(HOUR, purchased_on), site
ORDER BY
        label DESC