tiling shape files, or shptree

[Frank Warmerdam]

On 4/27/05, Tim Tsai <ttsai at pobox.com> wrote:
>   Thanks.  I am curious about that too.  So far, I have not run into
> performance problems with shptree alone but I might try shp2tile and
> see if there's a noticeable difference.
> 
>   My guess would be similar to the difference between a pure b-tree
> and a balanced b-tree or even a b+-tree.  Shp2tile keeps geographically
> related items together so you take advantage of the cluster effect and
> minimize the average seek times.  A balanced tree will give you much
> more deterministic response where an unbalanced tree could potentially
> have very bad performance in degenerate cases.

Tim / Schuyler, 

Yes, I've thought about that sometimes too.  It might be helpful to have
a tool that would would copy a shapefile in .qix traversal order.  That
is to reorder the features by locality as determined by the quadtree index.
That might given the convenient managability of one big shapefile 
with the locality benefits of tiling. 

Best regards,
-- 
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