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  1. Cassandra
  2. CASSANDRA-6048

Add the ability to use multiple indexes in a single query

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    • New Feature
    • Status: Resolved
    • Normal
    • Resolution: Duplicate
    • None
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    Description

      Existing data filtering uses the following algorithm

         1. find best selective predicate based on the smallest mean columns count
         2. fetch rows for the best selective predicate predicate, then filter the data based on other predicates left.
      

      So potentially we could improve the performance by

         1.  joining multiple predicates then do the data filtering for other predicates.
         2.  fine tune the best predicate selection algorithm
      

      For multiple predicate join, it could improve performance if one predicate has many entries and another predicate has a very few of entries. It means a few index CF read, join the row keys, fetch rows then filter other predicates

      Another approach is to have index on multiple columns.

      Attachments

        1. 6048-1.2-branch.txt
          29 kB
          Alex Liu
        2. 6048-trunk.txt
          18 kB
          Alex Liu

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              Unassigned Unassigned
              alexliu68 Alex Liu
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                Updated:
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