Select city/province
Seoul
Gyeonggi do
Incheon
Busan
Daegu
Daejeon
Gwangju
Ulsan
Gangwon do
Gyeongsangnam do
Gyeongsangbuk do
Jeollanam do
Jeollabuk do
Chungnam
Chungbuk
Jeju
Select gu/city
select s2 from Zip_e where s1 = '' group by s2 order by s2
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