You know the max deep of your tree.
In my case, 5 levels is the max, so it works ok.

Anyway, you reach the "usable" limit if you go deeper than 6 or 7 levels IMO.



>Hi Gerald,
>with integer primary keys I need 10 chars for concatenation (max = 2^32 = 4294967296 = 10 char long)
>
>What is the max length of a key in the treeview? 128 char or maybe 255???
>Either way this could be the limit on levels and I don't like limits
>
>Peter
>
>>>
>>>Or concatenate the keys
>>>
>>>
>>>I hope that clearifies the problem
>>>
>>>
>>>Peter
>>
>>
>>
>>Concatenation is a good solution.
>>I use it in one of my applications.
>>
>>I am using a fixed len key and concatenate it along the tree and the key was always unique.
>>This way, simply by usign the key I can say at which level I was and get the ID of every parent on the path.
>>
>>Example, with a 5 chars key, if you have "123AB123CD123EF" as a key, you know that you are at level 3 (len/5), the parent is "123CD" and the grand-parent is "123AB".