> > Links
> > -----
> > 1, 2
> > 2, 3
> > 1, 4
> > 1, 5
> > 1, 6
> >
> >
> > 4 childs for the same parent. item 2 has 1 child (which is item 3).
>
> OK, clear now... and what's the difference from Alexander solution,
> please?

In addition to other answers:

- it has no NULLs, which are nasty
- it should be easy to make it recursive
- you can do full "bill of material"s with it ( didn't check though ;)

With regards,

Martijn Tonies
Database Workbench - tool for InterBase, Firebird, MySQL, Oracle & MS SQL
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