http://forum.geonames.org/gforum/posts/list/9.page JForum - http://www.jforum.net 1 ; country | admin1 | count ---------+--------+------- GE | 00 | 2 IQ | 00 | 4 KH | 00 | 3 KI | 00 | 2 KZ | 00 | 5 LV | 00 | 4 MD | 00 | 17 ME | 00 | 19 MN | 00 | 2 NG | 00 | 7 NP | 00 | 14 PR | 00 | 13 PW | 00 | 11 SB | 00 | 7 ST | 00 | 2 TJ | 00 | 2 TL | 00 | 13 UG | 00 | 8 (18 rows) select country, admin1, admin2, count(*) from geoname where fclass='A' and fcode='ADM2' and admin2 is not null group by country, admin1, admin2 having count(*) > 1 ; country | admin1 | admin2 | count ---------+--------+--------+------- GB | ENG | 00 | 2 GB | ENG | F2 | 2 (2 rows) If I understand well '00' code is a non valid one : should it not be NULL as we do not have the information ? Here is a true duplicate : select * from geoname where fclass='A' and fcode='ADM2' and country='GB' and admin1='ENG' and admin2='F2'; geonameid | name | asciiname | alternatenames | latitude | longitude | fclass | fcode | country | cc2 | admin1 | a dmin2 | admin3 | admin4 | population | elevation | gtopo30 | timezone | moddate | geom -----------+---------------------+---------------------+--------------------------------------------------------------------------------------------------------------+------------+------------+--------+-------+---------+-----+--------+-- ------+--------+--------+------------+-----------+---------+---------------+------------+---------------------------------------------------- 2647554 | Hampshire | Hampshire | Hampshire,Hampshire County,Hants,Khehmpshir,Suthhamtunscir,Sūþhāmtūnscīr,Хэмпшир,ハンプシャー,ハンプシャー州 | 51 | -1.25 | A | ADM2 | GB | GB | ENG | F2 | | | 1691000 | | 77 | Europe/London | 2008-07-13 | 0101000020E6100000000000000000F4BF0000000000804940 2647555 | County of Hampshire | County of Hampshire | Hampshire | 51.0833333 | -1.1666667 | A | ADM2 | GB | GB | ENG | F 2 | | | 0 | | 77 | Europe/London | 2008-01-16 | 0101000020E6100000DE509DB3AAAAF2BF791563AAAA8A4940 (2 rows) Some more on 3rd level : select country, admin1, admin2, admin3, count(*) from geoname where fclass='A' and fcode='ADM3' and admin3 is not null group by country, admin1, admin2, admin3 having count(*) > 1 ; country | admin1 | admin2 | admin3 | count ---------+--------+--------+--------+------- DE | 14 | | 15171 | 2 ES | 31 | MU | 30030 | 2 ES | 34 | O | 33008 | 2 ES | 34 | O | 33032 | 2 ES | 34 | O | 33049 | 2 ES | 58 | OR | 32068 | 2 ES | 59 | BI | 48086 | 2 NO | 12 | 0301 | 13 | 2 (8 rows) On level 4 I did not fin any. ]]> http://forum.geonames.org/gforum/posts/list/1485.page#6190 http://forum.geonames.org/gforum/posts/list/1485.page#6190 GMT http://forum.geonames.org/gforum/posts/list/1485.page#6198 http://forum.geonames.org/gforum/posts/list/1485.page#6198 GMT http://forum.geonames.org/gforum/posts/list/1485.page#6216 http://forum.geonames.org/gforum/posts/list/1485.page#6216 GMT