CREATE TABLE "round_15" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "venue" text,
  "crowd" real,
  "date" text
);

Question: What was the away team's score at Princes Park?
SQL: SELECT "away_team" FROM "round_15" WHERE "venue"='princes park';

Question: When did Richmond play an away game against Collingwood?
SQL: SELECT "date" FROM "round_15" WHERE "away_team"='richmond';