hubert depesz lubaczewski, 21.04.2008 16:05:
>> ROOT, 1, NULL
>> CHILD1, 2, 1
>> CHILD2, 3, 1
>> I would have expected the following result:
>> ROOT, NULL
>> ROOT, CHILD1
>> ROOT, CHILD2
>> but the row with (ROOT,NULL) is not returned.
> why would you expect it?
> the columns are: parent and child (on your output).
> you dont have any row that has *parent_id = 1* and id = NULL.
Ah, of course that's where my mental block was ;)
Thanks for the quick response
> you can get this output though:
> NULL, ROOT
> ROOT, CHILD1
> ROOT, CHILD2
> with this query:
> select p.name as parent, c.name as child from category c left outer join category p on c.parent_id = p.id
If the table contains more levels (i.e. child1 being the parent of another item) this bring others back as well. And I was trying to retrieve the full path for each item (I do know the max. number of levels)
Cheers, and thanks a lot for the quick response
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