SQL Server 2017

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CREATE TABLE T
    ([id] int, [emp_id] int, [emp_name] varchar(3), [phone] int, [age] int)
;
    
INSERT INTO T
    ([id], [emp_id], [emp_name], [phone], [age])
VALUES
    (1, 101, 'aaa', 12345, 25),
    (2, 101, 'aaa', 34567, 30),
    (3, 102, 'bbb', 54325, 45)
;
3 rows affected

SELECT T.*
FROM T JOIN 
(
  SELECT MIN(ID) ID,
         MIN(Age) Age,
         Emp_Id
  FROM T
  GROUP BY Emp_Id
) TT ON T.Id = TT.Id AND T.Age = TT.Age;


id
emp_id
emp_name
phone
age


1
101
aaa
12345
25

3
102
bbb
54325
45


SELECT id,	
       emp_id,	
       emp_name,	
       phone,	
       age
FROM 
(
  SELECT *, ROW_NUMBER() OVER(PARTITION BY Emp_Id ORDER BY Id) RN
  FROM T
) TT
WHERE RN = 1;


id
emp_id
emp_name
phone
age


1
101
aaa
12345
25

3
102
bbb
54325
45


SELECT T.*
FROM T LEFT JOIN T TT
ON T.Emp_Id = TT.Emp_Id
   AND
   T.Age > TT.Age
WHERE TT.Id IS NULL;


id
emp_id
emp_name
phone
age


1
101
aaa
12345
25

3
102
bbb
54325
45