SQL Server 2017

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CREATE TABLE UserData(UserId VARCHAR(7),ModiDate DATE,High FLOAT,Weight FLOAT,BMI FLOAT);
INSERT INTO UserData(UserId,ModiDate,High,Weight,BMI)
VALUES
('A','2018/08/11',180,60,20),
('A','2018/09/11',180,60,20),
('A','2018/10/11',185,65,25),
('B','2018/11/11',190,70,30);
4 rows affected

SELECT A.UserId,CONVERT(VARCHAR,A.ModiDate,111) AS ModiDate,A.High,A.Weight,A.BMI
FROM UserData AS A
INNER JOIN (
SELECT X.UserID,MAX(X.ModiDate) as MAXModiDate
FROM UserData AS X
WHERE 1=1
AND ModiDate BETWEEN '2018/08/11' AND '2018/11/11'
GROUP BY X.UserID
) AS B ON B.UserId=A.UserId AND B.MAXModiDate=A.ModiDate

UNION

SELECT C.UserId,CONVERT(VARCHAR,C.ModiDate,111) AS ModiDate,C.High,C.Weight,C.BMI
FROM UserData AS C
INNER JOIN (
SELECT Y.UserID,MIN(Y.ModiDate) as MINModiDate
FROM UserData AS Y
WHERE 1=1
AND ModiDate BETWEEN '2018/08/11' AND '2018/11/11'
GROUP BY Y.UserID
) AS D ON D.UserId=C.UserId AND D.MINModiDate=C.ModiDate

ORDER BY UserId,ModiDate


UserId
ModiDate
High
Weight
BMI


A
2018/08/11
180
60
20

A
2018/10/11
185
65
25

B
2018/11/11
190
70
30