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  1. Kudu
  2. KUDU-1639 Improve predicate pushdown
  3. KUDU-2875

Convert scans with IN-list predicates on primary key prefix to multiple scans with equality predicates

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    • Type: Sub-task
    • Status: Open
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: perf, tserver
    • Labels:
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      Description

      In the case that an IN predicate is applied to a prefix of the primary key (or to column N of a composite key with equality predicates present on all columns <N), the tserver can convert the IN-list into multiple ranges. For example, assume a PK (entity, timestamp) and the query 'select * where entity in (1,3) and timestamp > 10'. In this case, we can internally convert to two scans 'entity = 1 and timestamp > 10' and 'entity = 3 and timestamp > 10'. These can then be evaluated efficiently using the index.

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              • Assignee:
                Unassigned
                Reporter:
                tlipcon Todd Lipcon
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                • Created:
                  Updated: