CREATE TABLE table_204_800 (id DECIMAL, "rank" DECIMAL, "nation" TEXT, "gold" DECIMAL, "silver" DECIMAL, "bronze" DECIMAL, "total" DECIMAL)

what country had the top number of silver medals ?
SELECT "nation" FROM table_204_800 ORDER BY "silver" DESC LIMIT 1
SELECT "nation" FROM "table_204_800" ORDER BY "silver" DESC NULLS LAST LIMIT 1