CREATE TABLE table_204_158 (id NUMBER, "official name" CLOB, "designation" CLOB, "area km2" NUMBER, "population" NUMBER, "parish" CLOB)

which city has the least area
SELECT "official name" FROM table_204_158 ORDER BY "area km2" LIMIT 1
SELECT "official name" FROM "table_204_158" ORDER BY "area km2" FETCH FIRST 1 ROWS ONLY