Who were the runners-up for the FC Viktoria Plzeň club?
CREATE TABLE "performance_by_club" (
  "club" text,
  "winners" real,
  "runners_up" real,
  "winning_years" text,
  "runner_up_years" text
);
SELECT "runners_up" FROM "performance_by_club" WHERE "club"='fc viktoria plzeň';