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<div>>From: postgis-users <postgis-users-bounces@lists.osgeo.org> on behalf of Shaozhong SHI <shishaozhong@gmail.com>Sent: Monday, March 28, 2022 3:21 PMTo: PostGIS Users Discussion <postgis-users@lists.osgeo.org>Subject: Re: [postgis-users] Cut extent box2d
into small regular boxes, and iterate through each box of features</div>
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<div>>Hi, Lars,</div>
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<div>>Your points are very interesting.</div>
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<div>>How about the following alternative.</div>
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<div>>Use geohash to divide features into geographical groups.</div>
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<div>>Treat each group in turn.</div>
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<div>>How about that?</div>
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Hi</div>
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I have not used geohash my self, but that only seems work in degrees. I have not seen any big problems with spatial grids as we make them and it's fast since it can use indexes so I am not sure how geohash can help us to do this in a better way.
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About grids, we do not only use grid for distribution, but also in some case spatial operations. For instance when we compute gaps/overlaps.</div>
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For parrel work that you asked about in ealier mail, we use <a href="https://github.com/larsop/postgres_execute_parallel" id="LPNoLPOWALinkPreview">
https://github.com/larsop/postgres_execute_parallel</a> , this is solution based on dblink which again my cause security issues so as it is now this is temporary solution .
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Lars<br>
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