What's the lowest rank of a player who played in 2012?
CREATE TABLE "wins_over_top_10_players_per_season" (
  "player" text,
  "rank" real,
  "event" text,
  "surface" text,
  "score" text
);
SELECT MIN("rank") FROM "wins_over_top_10_players_per_season" WHERE "event"='2012';