model.xml
SELECT T1.C1, SUM(T1.C2) OVER (PARTITION BY T1.C1) C2
FROM ( VALUES
(CAST(-8.46 AS DOUBLE PRECISION), 30),
(CAST(-23.34 AS DOUBLE PRECISION), 15),
(CAST(0.0 AS DOUBLE PRECISION), 10),
(CAST(0.0 AS DOUBLE PRECISION), 20),
(CAST(NULL AS DOUBLE PRECISION), 5),
(CAST(-5.22 AS DOUBLE PRECISION), 40),
(CAST(-1.08 AS DOUBLE PRECISION), 18)
) T1 (C1, C2)
[SQL1].[C1]
[SQL1].[C2]