text: TRUNCATE TABLE crimes_for_month;
  INSERT INTO crimes_for_month (ward, fbi_code, year, month, crime_count) 
  SELECT ward, 
         fbi_code, 
         date_part('year', occurred_at) AS "year", 
         date_part('month', occurred_at) AS "month", 
         count(*) 
  FROM crimes
  GROUP BY ward, fbi_code, date_part('year', occurred_at), "month" 
  ORDER BY ward, fbi_code, year, month
  ;
  