Coba pilih duplikatnya dulu, hapus saja
DELETE FROM usa_city WHERE city_id IN
(
SELECT city_id FROM usa_city
GROUP BY city_name, id_state
HAVING count(city_id) > 1
)
Semoga membantu!!!
DIMODIFIKASI:Berdasarkan komentar, jika Anda ingin menyimpan satu catatan , Anda dapat bergabung dan mempertahankan nilai terendah
DELETE c1 FROM usa_city c1, usa_city c2 WHERE c1.id < c2.id AND
(c1.city_name= c2.city_name AND c1.id_state = c2.id_state)
Pastikan untuk membuat cadangan sebelum menjalankan kueri di atas...
