SQL Server 2017

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CREATE TABLE TestResults (
MeterSN Varchar(20) NULL ,     
LotNumber Varchar(20) NULL,      
DateTime_ID DateTime NULL,      
BAY Varchar(20) NULL);     

INSERT INTO TestResults (MeterSN,LotNumber,DateTime_ID,BAY)
VALUES 
('h01934245','P0401','2021-04-26 02:27:42.227','3'),
('h01934245','P0401','2021-04-26 03:47:13.003','6'),
('h01934245','P0402','2021-03-20 04:27:42.227','7'),
('h01934246','X0401','2021-03-10 05:27:42.227','1'),
('h01934246','X0401','2021-03-12 06:27:42.227','2');

SELECT MeterSN,LotNumber,DateTime_ID, BAY
FROM TestResults;


MeterSN
LotNumber
DateTime_ID
BAY


h01934245
P0401
2021-04-26 02:27:42.227
3

h01934245
P0401
2021-04-26 03:47:13.003
6

h01934245
P0402
2021-03-20 04:27:42.227
7

h01934246
X0401
2021-03-10 05:27:42.227
1

h01934246
X0401
2021-03-12 06:27:42.227
2


-- 方法一
SELECT MeterSN,LotNumber,DateTime_ID,BAY
FROM (
SELECT ROW_NUMBER() OVER (PARTITION BY MeterSN,LotNumber ORDER BY DateTime_ID DESC) AS ROWNUM,*
FROM TestResults) AS TempM
WHERE ROWNUM = 1
ORDER BY MeterSN,LotNumber 


MeterSN
LotNumber
DateTime_ID
BAY


h01934245
P0401
2021-04-26 03:47:13.003
6

h01934245
P0402
2021-03-20 04:27:42.227
7

h01934246
X0401
2021-03-12 06:27:42.227
2


-- 方法二
SELECT TestResults.MeterSN,TestResults.LotNumber,TestResults.DateTime_ID,TestResults.BAY
FROM TestResults
INNER JOIN (
SELECT MeterSN,LotNumber,MAX(DateTime_ID) AS DateTime_ID
FROM TestResults
GROUP BY MeterSN,LotNumber) AS Temp ON Temp.MeterSN=TestResults.MeterSN 
AND Temp.LotNumber=TestResults.LotNumber
AND Temp.DateTime_ID=TestResults.DateTime_ID
ORDER BY TestResults.MeterSN,TestResults.LotNumber


MeterSN
LotNumber
DateTime_ID
BAY


h01934245
P0401
2021-04-26 03:47:13.003
6

h01934245
P0402
2021-03-20 04:27:42.227
7

h01934246
X0401
2021-03-12 06:27:42.227
2

MeterSN	LotNumber	DateTime_ID	BAY
h01934245	P0401	2021-04-26 02:27:42.227	3
h01934245	P0401	2021-04-26 03:47:13.003	6
h01934245	P0402	2021-03-20 04:27:42.227	7
h01934246	X0401	2021-03-10 05:27:42.227	1
h01934246	X0401	2021-03-12 06:27:42.227	2