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Use a geohash index when clustering tables in the optimization phase #15

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tbonfort opened this issue Sep 27, 2012 · 2 comments
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@tbonfort
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c.f. http://workshops.opengeo.org/postgis-intro/clusterindex.html

will submit a PR if it has a chance of being integrated

@olt
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olt commented Sep 27, 2012

Cool finding! It says that "an R-Tree built incrementally on spatial data might not have high spatial coherence of the leaves". Does this also apply when the index was created on a full dataset?

@pramsey can you answer that?

If not, then we don't need this with your change #14. Otherwise a patch would be welcomed (maybe with ST_Centroid before ST_Transform).

@pramsey
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pramsey commented Sep 28, 2012

Yes, the effect can be the same either way. Data with highly variable
density will show this effect more than homogeneous data. I wouldn't
necessarily expect any huge performance gains from clustering though, these
are all improvements on the margins.
P.

On Thu, Sep 27, 2012 at 2:10 AM, Oliver Tonnhofer
[email protected]:

Cool finding! It says that "an R-Tree built incrementally on spatial data
might not have high spatial coherence of the leaves". Does this also apply
when the index was created on a full dataset?

@pramsey https://github.com/pramsey can you answer that?

If not, then we don't need this with your change #14#14.
Otherwise a patch would be welcomed (maybe with ST_Centroid before
ST_Transform).


Reply to this email directly or view it on GitHubhttps://github.com//issues/15#issuecomment-8930319.

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