The effectiveness of this approach, for both query performance and compression, relies on the user selecting good primary key columns via the ORDER BY clause when creating a table. In general, users should select columns for which they will often filter tables with more than 2 to 3 columns rarely required. The order of these columns is critical and can affect the compression and filtering by columns other than the first entry. For both the efficient filtering of secondary key columns in queries and the compression ratio of a table's column files, it is optimal to order the columns in a primary key by their cardinality in ascending order. A full explanation of the reasoning can be found here.
Checking to see what bits hit an entry isn’t
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