Question

Need help on a query to sum all values by month grouped by comma

Trying:

SELECT GROUP_CONCAT( (
    SELECT SUM( price ) 
    FROM sales
    GROUP BY MONTH( date ) )
    )
FROM sales
LIMIT 0 , 30

but returning: #1242 – Subquery returns more than 1 row

group_concat alone won’t help cause I need the sum of the values by month.

Any help? Thanks

Answer 1

Untested:

SELECT GROUP_CONCAT(a.totprice) 
FROM (
  SELECT SUM(price) as totprice
  FROM sales
  GROUP BY MONTH(date)
) a;

Note that you will get max 12 values, since any different years are merged. You probably want to add an ORDER BY in the subquery to get the months in a defined order in the result.