Name the sum of silver when total is mor ethan 1, bronze is 1 and gold is les than 0
CREATE TABLE "performance_by_nation" (
  "rank" real,
  "gold" real,
  "silver" real,
  "bronze" real,
  "total" real
);
SELECT SUM("silver") FROM "performance_by_nation" WHERE "total">1 AND "bronze"=1 AND "gold"<0;