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From Jon Haddad <jonathan.had...@gmail.com>
Subject Re: Smart Table creation for 2D range query
Date Tue, 09 May 2017 03:13:57 GMT
It gets a little tricky when you try to add in the coordinates to the clustering key if you
want to do operations that are more complex.  For instance, finding all the elements within
a radius of point (x,y) isn’t particularly fun with Cassandra.  I recommend moving that
logic into the application.  

> On May 8, 2017, at 10:06 PM, kurt greaves <kurt@instaclustr.com> wrote:
> 
> Note that will not give you the desired range queries of 0 >= x <= 1 and 0 >=
y <= 1.
> 
> 
> ​Something akin to Jon's solution could give you those range queries if you made the
x and y components part of the clustering key.
> 
> For example, a space of (1,1) could contain all x,y coordinates where x and y are >
0 and <= 1. You would then have a table like:
> 
> CREATE TABLE geospatial (
> space text,
> x double,
> y double,
> item text,
> m1,
> m2,
> m3,
> primary key ((space), x, y, m1, m2, m3, m4, m5)
> );
> 
> A query of select * where space = '1,1' and x <1 and x >0.5 and y< 0.2 and y>0.1;
should yield all x and y pairs and their distinct metadata. Or something like that anyway.
> 


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