Find and delete duplicate data in mysql postgresql

gistfile1.txt

==mysql
SELECT employee_id, date FROM attendance group by date,employee_id having count(*) >= 2

DELETE t1 FROM attendance t1
INNER JOIN attendance t2 
WHERE 
    t1.id < t2.id AND 
    t1.employee_id = t2.employee_id AND 
	t1.date = t2.date
;


==postgresql

SELECT
    employee_id, date,
    COUNT( employee_id)
FROM
    attendance 
GROUP BY
    employee_id, date
HAVING
    COUNT( employee_id)> 1
ORDER BY
    employee_id



DELETE FROM
    attendance a
        USING attendance b
WHERE
    a.id < b.id
    AND a.employee_id = b.employee_id
	AND a.date = b.date
;