CREATE TABLE X(ID INT IDENTITY(1,1), DT DATETIME, VAL NVARCHAR(10), AMOUNT DECIMAL(18,4))

INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-01', N'Коровы', 10.5)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-02', N'Куры', 150.2)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-03', N'Свиньи', 70.1)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-04', N'Голуби', 7)

DELETE FROM X WHERE DT >= '2020-01-02'

INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-02', N'Куры', 150.2)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-03', N'Свиньи', 76.1)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-03', N'Овцы', 66.7)

SELECT * FROM X
GO 
DROP TABLE X
GO 

CREATE TABLE X(ID INT IDENTITY(1,1), DT DATETIME, VAL NVARCHAR(10), AMOUNT DECIMAL(18,4))
GO
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-01', N'Коровы', 10.5)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-02', N'Куры', 150.2)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-03', N'Свиньи', 70.1)
INSERT INTO X(DT, VAL, AMOUNT) VALUES('2020-01-04', N'Голуби', 7)

MERGE X AS Target
USING (
	SELECT * FROM (
		VALUES(	'2020-01-02', N'Куры', 150.2),
				('2020-01-03', N'Свиньи', 76.1),
				('2020-01-03', N'Овцы', 66.7)
	) Source(DT, VAL, AMOUNT) 
) AS Source ON Source.DT = Target.DT AND Source.VAL = Target.VAL
WHEN MATCHED AND Target.DT >= '2020-01-02' AND Target.AMOUNT <> Source.AMOUNT THEN 
    UPDATE SET Target.AMOUNT = Source.AMOUNT
WHEN NOT MATCHED BY SOURCE AND Target.DT >= '2020-01-02' THEN 
    DELETE 
WHEN NOT MATCHED BY TARGET THEN 
    INSERT (DT, VAL, AMOUNT) VALUES(DT, VAL, AMOUNT)
;

SELECT * FROM X

GO 
DROP TABLE X