Question

In the DataBase i Stored the Some information(represented in the Attached ScreenShot)

what is the best way to get the longest hierarchy id?
in the attached pic the longest hierarchy is 128 ,because it has the least number of 0’s values in it’s fields(t_definition_types_id_(1-4))

Thank You

Answer 1

another way is like :

SELECT id,
 (IF(t_definition_types_id_1>0, 1, 0) + 
  IF(t_definition_types_id_2>0, 1, 0) +
  IF(t_definition_types_id_3>0, 1, 0) +
  IF(t_definition_types_id_4>0, 1, 0) 
) 
AS level 
FROM mytable ORDER BY level DESC