Getting Up Level

Getting Up Level

Leveling Database structure, is maight be not awkward for many programmer. I got problem when getting the up/upper level of some code. At last I found this way :


Suppose you have a data structure like this:

code varchar(10)
name varchar(100)
parent varchar(10)
level integer

code name parent level
------------------------------------
A1 AOne 1
A10 AOnezero A1 2
A11 AOneOne A1 2
A110 AOneOnezero A11 3


what is the up level 1 code of A110?

answer:
make the sql like this:
select * from table where level=1 and 'A110' like concat(code,'%')