MySQL sub position counters in Query

I need to get a record set where I fill the field level1 for every 60 records, means I need to fill level1 field this way:

• on pos=1 and pos=60 with level1 = 1
• on pos=61 and pos=120 with level1 = 2
• on pos=121 and pos=180 with level1 = 3

... and then: if I have let's say 630 records i must set for pos=601 and 630 level1 = 10 because I don't have 660 records the 630th record finished the level.

Has anyone a idea how this can be done in a clean way?

SET @pos:=0; 
SET @posrel:=0;
SET @level1:=0;
SELECT id, member_id, member_name, pos, @posrel:=@posrel+1 AS posrel, @level1:=@level1+??? AS 开发者_StackOverflow社区level1
FROM
(
  SELECT id, member_id, LEFT(member_name, LENGTH(member_name)-36) AS member_name, @pos:=@pos+1 AS pos FROM member_directory WHERE member_name_first= 'A'
) AS directory_listing
HAVING pos % 60 IN(0,1);

---

-- SET @pos:=0;   //Can be moved inside the query.
-- SET @posrel:=0; 
SELECT inner.*, posrel DIV 60 as level1 FROM (
  SELECT directory_listing.*, @posrel:=@posrel+1 AS posrel  AS level1
  FROM
  (
    SELECT 
      id
      , member_id
      , LEFT(member_name, LENGTH(member_name)-36) AS member_name_first
      , @pos:=@pos+1 AS pos 
    FROM member_directory
    CROSS JOIN (SELECT @pos:= 0) x1  
    WHERE member_name_first = 'A'
    AND directory_listing.pos < 120
  ) directory_listing
  CROSS JOIN (SELECT @posrel:= 0) x2
) inner

Or maybe

-- SET @pos:=0;   //Can be moved inside the query.
-- SET @posrel:=0; 
SELECT inner.*, posrel DIV 60 as level1 FROM (
  SELECT directory_listing.*, @posrel:=@posrel+1 AS posrel  AS level1
  FROM
  (
    SELECT 
      id
      , member_id
      , LEFT(member_name, 1) AS member_name_first
      , @pos:=@pos+1 AS pos 
    FROM member_directory
    CROSS JOIN (SELECT @pos:= 0) x1  
    WHERE member_name LIKE 'A%'
    AND directory_listing.pos < 120
  ) directory_listing
  CROSS JOIN (SELECT @posrel:= 0) x2
) inner