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  1. Kylin
  2. KYLIN-4189

Prevent abnormal CPU usage by limiting lookup table's rows

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    Details

    • Type: Improvement
    • Status: Open
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: v2.4.0, v2.5.0, v2.6.0
    • Fix Version/s: None
    • Component/s: Query Engine
    • Labels:
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      Description

      Although lookup table size is limited, snapshot table with too many rows will break the server.

      Such as:

      select
        dim.b
      FROM
        fact
        INNER JOIN dim ON fact.B = dim.B
      group by
        dim.b
      

      If the number of rows in column dim.B is million, the query will execute for dozens seconds and the CPU utilization is extremely high.

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            • Assignee:
              temple.zhou Temple Zhou
              Reporter:
              temple.zhou Temple Zhou
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              Dates

              • Created:
                Updated: