Page Comparison

Cone Searching & HTM

Many of the queries we want to do are related to the position of objects in the sky. We use HTM - Hierarchical Triangular Mesh - to index the sky and utilise the API to augment our SQL queries. In this document I will attempt to use HTM with Cassandra. This may of course be a bad match of technologies (see issues below), and there may be other spatial indexing technologies that tie in better with Cassandra.

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select * from tcs_cat_gaia_dr2 where htm10 IN ('S23023222101','S23023222132')
AND (htm13) IN
('000','001','002','003');

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