text: begin;
  
  create index pk_idx
  on ncaa_pbp.periods (game_id,section_id);
  
  delete from ncaa_pbp.periods per
  where per.ctid <>
  (select min(dup.ctid)
   from ncaa_pbp.periods dup
   where (dup.game_id,dup.section_id) =
         (per.game_id,per.section_id)
  );
  
  drop index ncaa_pbp.pk_idx;
  
  commit;
  