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Here is the code to create the sample data:

CREATE TABLE students (
id INT PRIMARY KEY,
name VARCHAR(50) NOT NULL,
age INT NOT NULL
);

INSERT INTO students (id, name, age)
VALUES
(1, 'Alice', 20),
(2, 'Bob', 22),
(3, 'Charlie', 20),
(4, 'Alice', 20),
(5, 'David', 18),
(6, 'Charlie', 20),
(7, 'Eve', 19),
(8, 'Bob', 22),
(9, 'Frank', 21);

Here is the query:
SELECT id, name, age
FROM (
SELECT id, name, age, COUNT(*) OVER (PARTITION BY name, age) AS cnt
FROM students
) sub
WHERE cnt ;gt; 1;



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