CREATE TABLE table_204_311 (id NUMBER, "rank" NUMBER, "nation" CLOB, "gold" NUMBER, "silver" NUMBER, "bronze" NUMBER, "total" NUMBER)

which nations had a gold medal but no silver medals ?
SELECT "nation" FROM table_204_311 WHERE "gold" = 1 AND "silver" = 0
SELECT "nation" FROM "table_204_311" WHERE "gold" = 1 AND "silver" = 0