CREATE TABLE "round_4" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "venue" text,
  "crowd" real,
  "date" text
);

Question: Who was the home team at Princes Park?
SQL: SELECT "home_team_score" FROM "round_4" WHERE "venue"='princes park';