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  1. Hive
  2. HIVE-22658

calite for hive struct Ineffective optimization

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Details

    • Bug
    • Status: Open
    • Blocker
    • Resolution: Unresolved
    • 2.3.2, 2.3.3, 3.1.1
    • None
    • CBO
    • None

    Description

      student table:

      CREATE TABLE `student`(
        `id` int, 
        `info` struct<name:string,age:int>)
      ROW FORMAT SERDE 
        'org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe' 
      WITH SERDEPROPERTIES ( 
        'colelction.delim'=':', 
        'field.delim'=',', 
        'serialization.format'=',', 
        'serialization.null.format'='NULL')  
      

      the sql:

       

      select * from student where info is not null;
      

      result:

       

      1       {"name":"zhou","age":30}
      2       {"name":"yan","age":30}
      3       {"name":"chen","age":20}
      4       {"name":"li","age":80}
      NULL    NULL
      NULL    {"name":null,"age":null}
      

      cause:calcite Ineffective optimization

       cbo execute plan:

      HiveProject(id=[$0], info=[$1]) 
        HiveTableScan(table=[[default.student]], table:alias=[student])
      

      after fix RelRecordType isNullable,the plan is

      cbo execute plan:

      HiveProject(id=[$0], info=[$1])
        HiveFilter(condition=[IS NOT NULL($1)])
          HiveTableScan(table=[[default.student]], table:alias=[student])
      

      then the result is:

      1 {"name":"zhou","age":30} 
      2 {"name":"yan","age":30} 
      3 {"name":"chen","age":20} 
      4 {"name":"li","age":80}
      NULL    {"name":null,"age":null}
      
      

       

      Attachments

        1. calcite-3608.patch
          0.5 kB
          hezhang

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              Unassigned Unassigned
              heiheizhang hezhang
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              Dates

                Created:
                Updated: