CREATE TABLE visitors_daily (
  visitor_id TEXT NOT NULL,
  visit_date TEXT NOT NULL,
  first_seen_at TEXT NOT NULL,
  last_seen_at TEXT NOT NULL,
  PRIMARY KEY (visitor_id, visit_date)
);
CREATE INDEX visitors_daily_visit_date ON visitors_daily (visit_date);
CREATE TABLE arrivals (
  dog_id TEXT PRIMARY KEY NOT NULL,
  first_arrived_at TEXT NOT NULL
);