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DECLARE @T table
(
EntryDate datetime2(0) NOT NULL,
Purchase money NULL,
Sale money NULL
);
INSERT @T
(EntryDate, Purchase, Sale)
VALUES
('20180801 13:00:00', 1000, NULL),
('20180801 14:00:00', NULL, 400),
('20180801 15:00:00', NULL, 400),
('20180801 16:00:00', 5000, NULL);
SELECT
T.Purchase,
T.Sale,
Remaining =
SUM(ISNULL(T.Purchase, $0) - ISNULL(T.Sale, 0)) OVER (
ORDER BY T.EntryDate
ROWS UNBOUNDED PRECEDING)
FROM @T AS T;
| Purchase | Sale | Remaining |
|---|---|---|
| 1000.0000 | null | 1000.0000 |
| null | 400.0000 | 600.0000 |
| null | 400.0000 | 200.0000 |
| 5000.0000 | null | 5200.0000 |