How to get the max() amount from a sum() subquery

Question

My sub-query gets me the brand name and sum of the of the sales amount from 2013. My main query is trying to get the brand name and the highest sales amount from that year but this will return duplicate because the query will try to get the max(amount) for each brand name. How do I filter it so it will just return the highest amount with only one brand name? This is my query so far, any pointers would be helpful. Thanks!

SELECT
maxamt.brnd_nm, 
MAX(maxamt.amt) AS amt


FROM
(
SELECT 
c.brnd_nm AS BRND_NM,
SUM(b.sales_amt) AS AMT

FROM prd.client  A

INNER JOIN db1.table1  B
ON b.pty_key = a.pty_key
INNER JOIN db1.table2 c
ON b.d_key = c.d_key
INNER JOIN db1.table3 d
ON b.posat_key = d.posat_key
INNER JOIN db1.table4 e
ON b.frmly_key = e.frmly_key
WHERE   B.date BETWEEN '2013-01-01' 
    AND '2013-12-31'
    AND b.C_ID IN ( 'abc', 'def', 'wqs')

GROUP BY 1
) MaxAmt
GROUP BY 1

Answer 1

You don't need a subquery, just use ORDER BY and LIMIT :

SELECT 
    c.brnd_nm AS BRND_NM,
    SUM(b.sales_amt) AS AMT

FROM prd.client  A

INNER JOIN db1.table1  B
    ON b.pty_key = a.pty_key
INNER JOIN db1.table2 c
    ON b.d_key = c.d_key
INNER JOIN db1.table3 d
    ON b.posat_key = d.posat_key
INNER JOIN db1.table4 e
    ON b.frmly_key = e.frmly_key
WHERE   B.date BETWEEN '2013-01-01' 
    AND '2013-12-31'
    AND b.C_ID IN ( 'abc', 'def', 'wqs')

GROUP BY BRND_NM
ORDER BY AMT DESC
LIMIT 1

Answer 2

Can't you use the TOP operator?:

SELECT TOP 1 *
FROM (  SELECT  c.brnd_nm AS BRND_NM,
                SUM(b.sales_amt) AS AMT
        FROM prd.client  A
        INNER JOIN db1.table1  B
            ON b.pty_key = a.pty_key
        INNER JOIN db1.table2 c
            ON b.d_key = c.d_key
        INNER JOIN db1.table3 d
            ON b.posat_key = d.posat_key
        INNER JOIN db1.table4 e
            ON b.frmly_key = e.frmly_key
        WHERE   B.date BETWEEN '2013-01-01' 
            AND '2013-12-31'
            AND b.C_ID IN ( 'abc', 'def', 'wqs')

        GROUP BY c.brnd_nm) MaxAmt
ORDER BY AMT DESC

Answer 3

You can use QUALIFY plus ROW_NUMBER:

SELECT 
c.brnd_nm AS BRND_NM,
SUM(b.sales_amt) AS AMT

FROM prd.client  A

INNER JOIN db1.table1  B
ON b.pty_key = a.pty_key
INNER JOIN db1.table2 c
ON b.d_key = c.d_key
INNER JOIN db1.table3 d
ON b.posat_key = d.posat_key
INNER JOIN db1.table4 e
ON b.frmly_key = e.frmly_key
WHERE   B.date BETWEEN '2013-01-01' 
    AND '2013-12-31'
    AND b.C_ID IN ( 'abc', 'def', 'wqs')

GROUP BY 1
QUALIFY
   ROW_NUMBER() 
   OVER (ORDER BY AMT DESC) = 1