SQL query - Sum of total refund amount
I want to get the total refund amount in the last 365 days. However, This return the total refund amount (not last 365 days only). What should be the right way to do this?
SELECT sum(a.total_amount) AS TotalRefund365Days from [dbo].[UserPurchase] a inner join [dbo].[UserPurchaseRefunds] b on a.user_purchase_id = b.user_purchase_id where a.is_refunded = 1 AND b.DateCreated > (getdate() - 365)
Note: ([dbo].[UserPurchaseRefunds].Amount is total purchase quantity which is not required)
I think your issue is what David Browne pointed out in your other post regarding this, which is your relationship between the
dbo.UserPurchaseRefundsis one-to-many. This results in your current query are double counting the
What you want to do is use a CTE or subquery to de-dupe the redundant rows first, then aggregate the remaining rows, like so:
SELECT SUM(RefundedAmounts.total_amount) AS TotalRefund365Days FROM ( SELECT a.total_amount FROM dbo.UserPurchase a INNER JOIN dbo.UserPurchaseRefunds b ON a.user_purchase_id = b.user_purchase_id WHERE a.is_refunded = 1 AND b.DateCreated > (GETDATE() - 365) GROUP BY a.user_purchase_id, a.total_amount ) AS RefundedAmounts