Cone Searching & HTM
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Partition Keys and Clustering Keys
Cassandra will now NOT allow you to query any old column with any constraint. Unlike databases, you have to build the column families (tables) with the query in mind, otherwise you can’t easily pull out the information you need. Let’s take a look at a row of the Gaia DR2 table. The unique identifier column is “source_id”. But this doesn’t mean much in terms of organising the data.
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Decimal | Binary | Base4 | |
|---|---|---|---|
HTM16 | 54680902005 | 110010111011001111000101100101110101 | N02323033011211311 |
HTM13 | 854389093 | 110010111011001111000101100101 | N02323033011211 |
HTM10 | 13349829 | 110010111011001111000101 | N02323033011 |
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