>>Hi,
>>
>>I posted the following in the .NET forum but it's essentially a SQL query problem so I thought I'd try here as well:
>>--------------->
>>Assume a table where each row contains the specification for a rectangle but which also may 'inherit' from a parent row. E.g.:
>>
>>ID ParentID Top Left Width Height Color
>>1 0 10 10 100 100 White
>>2 1 null null 200 null null
>>3 2 null null null null Red
>>4 1 20 20 null null Green
>>* where non-null values override the parent value. This means ID 3 would be:
>> 10 10 200 100 Red
>>* ID 4 would be:
>> 20 20 100 100 Green
>>* etc
>>
>>I had this coded in VFP using recursion to 'walk' back up the tree to the root record and then build the final spec by unwinding back down. Any suggestion on how to implement this using ADO/SQLServer (with as much as possible in SQL since this data may also be accessed by other front ends)?
>>
>>Bear in mind that the example above is a (gross) over-simplification of the actual table structure and that the nesting levels will often be deeper...
>>
>>TIA,
>>Viv
>
>
>SELECT *, 0 done FROM table where .... into #temp
>:loopwhile rowCount>0
> update #temp
> set done=1
> , Top = coalesce(Top,T.Top)
> , ...
> FROM table T WHERE #temp.done=0 AND T.id = #temp.ParentID
>:loopend
>SELECT * FROM #TEMP
>
Hi Fabio,
Thanks - I couldn't get this to work from your code (maybe I misunderstood something) but it gave me a direction. I'm testing the following at the moment. Do you see any problems ?
CREATE PROCEDURE test @id int AS
SELECT * into #temp FROM Rects WHERE id=@id
WHILE @@ROWCOUNT > 0
BEGIN
UPDATE #temp
SET ParentID = T.Parentid
, rtop = coalesce(#temp.rtop,T.rtop)
,rleft = coalesce(#temp.rleft,T.rleft)
,rwidth = coalesce(#temp.rwidth,T.rwidth)
,rheight = coalesce(#temp.rheight,T.rheight)
, colour = coalesce(#temp.colour,T.colour,'')
FROM Rects T WHERE T.id = #temp.ParentID
END
SELECT * FROM #TEMP
GORegards,
Viv
