SQLite Forum

I found a faster solution for "select max(ID) from t group by GroupID LIMIT 1);".


create trigger t_bi_prune before insert on t
begin
  delete from t
    where ID = (
      select ID from t as o  
      where 
       (select count(ID) from t where GroupID  == o.GroupID ) > 1 
	and Ack != 1
	except 
	select ID from t as o  
        where ID = (select ID from t where GroupID  = o.GroupID  order by ID desc limit 1) order by ID limit 1;
end

4000 rows - insert one row : needs around 0.002 sec