CREATE TABLE table_12485020_1 (ds_division VARCHAR2, main_town VARCHAR2)

Kaluvanchikudy is the main town in what DS division?
SELECT ds_division FROM table_12485020_1 WHERE main_town = "Kaluvanchikudy"
SELECT "ds_division" FROM "table_12485020_1" WHERE "Kaluvanchikudy" = "main_town"