What is the total number of silver medals for karate athletes with over 2 golds?
CREATE TABLE "multiple_asian_games_gold_medalists" (
  "athlete" text,
  "sport" text,
  "asian_games" text,
  "gold" real,
  "silver" real,
  "bronze" real,
  "total" real
);
SELECT COUNT("silver") FROM "multiple_asian_games_gold_medalists" WHERE "sport"='karate' AND "gold">2;