DECLARE @Customer VARCHAR(50)
SET @Customer=$[OINV.CardCode]
SELECT
ISNULL((SELECT SUM(T0.DocTotal) FROM OINV T0 WHERE T0.[DocDate]>'20230401' AND T0.[CANCELED]='N' AND T0.CardCode=@Customer),0) - ISNULL( (SELECT -SUM(T0.DocTotal) FROM ORIN T0 WHERE T0.[DocDate]>'20230401' AND T0.[CANCELED]='N' AND T0.CardCode=@Customer),0)
[TurnOver]