SUM all prices from table SQL - sql

Question

i have following SQL query which is summing tourist tax from selected period.
SELECT
BTR_DESCRIPTION AS TOURIST_TAX_NAME,
ISNULL(BREAG_TOURIST_TAX_PRICE,0) AS PRICE,
SUM(DATEDIFF(d, BRE_DATEFROM, BRE_DATETO)) AS QUANTITY,
ISNULL(BREAG_TOURIST_TAX_PRICE,0) * SUM(DATEDIFF(d, BRE_DATEFROM, BRE_DATETO)) AS FINAL_PRICE
FROM BOS_RESERVATION
LEFT OUTER JOIN BOS_RESADDGUEST ON BREAG_BRE_ID = BRE_ID
LEFT OUTER JOIN BOS_TAX_REASONS ON BTR_ID = BREAG_BTR_ID
WHERE BREAG_DATEFROM >= '2018-02-28' AND BREAG_DATETO <= '2018-03-31'
GROUP BY BTR_DESCRIPTION, BREAG_TOURIST_TAX_PRICE
Query result:
Now i want to sum all values from FINAL_PRICE row. So the result must be: 5,652
But i dont know how to do this. I tried with following SQL:
SUM(ISNULL(BREAG_TOURIST_TAX_PRICE,0) * SUM(DATEDIFF(d, BRE_DATEFROM, BRE_DATETO))) AS FINAL_PRICE_SUM
But this gives me error: Cannot perform an aggregate function on an expression containing an aggregate or a subquery.
Can you please help me how to sum all values from FINAL_PRICE row?
Thanks!

Answer 1

You can do it like this:
WITH AggregatedTable as (SELECT
BTR_DESCRIPTION AS TOURIST_TAX_NAME,
ISNULL(BREAG_TOURIST_TAX_PRICE,0) AS PRICE,
SUM(DATEDIFF(d, BRE_DATEFROM, BRE_DATETO)) AS QUANTITY,
ISNULL(BREAG_TOURIST_TAX_PRICE,0) * SUM(DATEDIFF(d, BRE_DATEFROM, BRE_DATETO)) AS FINAL_PRICE
FROM BOS_RESERVATION
LEFT OUTER JOIN BOS_RESADDGUEST ON BREAG_BRE_ID = BRE_ID
LEFT OUTER JOIN BOS_TAX_REASONS ON BTR_ID = BREAG_BTR_ID
WHERE BREAG_DATEFROM >= '2018-02-28' AND BREAG_DATETO <= '2018-03-31'
GROUP BY BTR_DESCRIPTION, BREAG_TOURIST_TAX_PRICE)
Select at.*,
(SELECT SUM(FINAL_PRICE) from AggregatedTable)) as Total_FP
from AggregatedTable AS at

Answer 2

If you want the total final price, use a CTE or subquery:
WITH r as (
SELECT BTR_DESCRIPTION AS TOURIST_TAX_NAME,
COALESCE(BREAG_TOURIST_TAX_PRICE, 0) AS PRICE,
SUM(DATEDIFF(day, BRE_DATEFROM, BRE_DATETO)) AS QUANTITY,
COALESCE(BREAG_TOURIST_TAX_PRICE, 0) * SUM(DATEDIFF(day, BRE_DATEFROM, BRE_DATETO)) AS FINAL_PRICE
FROM BOS_RESERVATION LEFT OUTER JOIN
BOS_RESADDGUEST
ON BREAG_BRE_ID = BRE_ID LEFT OUTER JOIN
BOS_TAX_REASONS
ON BTR_ID = BREAG_BTR_ID
WHERE BREAG_DATEFROM >= '2018-02-28' AND BREAG_DATETO <= '2018-03-31'
GROUP BY BTR_DESCRIPTION, BREAG_TOURIST_TAX_PRICE
)
SELECT SUM(FINAL_PRICE)
FROM r;