create table data (
  id    int,
  stage varchar(255),
  name  varchar(255)
);

 id    stage      name
 ----------------------------
 1   pyramid     act 1
 2   pyramid     act 2
 3   NULL        act 3
 4   NULL        act 4
 5   NULL        act 5
 6   NULL        act 6
 7   NULL        act 7
 8   NULL        act 8
 9   NULL        act 9
 10  NULL        act 10
 11  NULL        act 11
 12  NULL        act 12
 13  shangri la  act 13

select *
from data
order by stage asc nulls first
limit 5;

id    stage      name
 ----------------------------
 6     NULL       act 6
 3     NULL       act 3
 4     NULL       act 4
 5     NULL       act 5
 7     NULL       act 7
 ----------------------------

select *
from data
order by stage asc nulls first
limit 3;

id    stage      name
 ----------------------------
 4     NULL       act 4
 3     NULL       act 3
 5     NULL       act 5
 ----------------------------