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  1. Apache Drill
  2. DRILL-2267

Parquet writer with dictionary encoding results in corrupted varchar columns

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    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 0.8.0
    • Component/s: Storage - Parquet
    • Labels:
      None

      Description

      Using CTAS created a parquet file through drill having the varchar datatype.

      Created parquet file looks like this through parquet-tools
      VARCHAR_col: OPTIONAL BINARY O:UTF8 R:0 D:1
      VAR16CHAR_col: OPTIONAL BINARY O:UTF8 R:0 D:1

      VARCHAR_col: BINARY SNAPPY DO:0 FPO:894307 SZ:16344/231716/14.18 VC:378624 ENC:RLE,PLAIN_DICTIONARY,BIT_PACKED
      VAR16CHAR_col: BINARY SNAPPY DO:0 FPO:910651 SZ:25830/381493/14.77 VC:378624 ENC:RLE,PLAIN_DICTIONARY,BIT_PACKED

      On querying the file several records show up having corrupted data for these fields.

      VAR16CHAR_col

      ---------------

      ������������
       
      ��������
      �����
      ��
       
       
      ��
      ������������
       
      ��������
      �����
      ��
       
       
      ��
      ������������
       
      ��������
      �����
      ��
       
       
      ��
      ������������
       
      ��������
      �����
      ��
       
       
      ��
      ������������
       
      ��������
      �����
      ��

      If dictionary encoding is turned off the resultant file can be read without these issues.

        Attachments

        1. 0_0_0.parquet
          946 kB
          Ramana Inukonda Nagaraj
        2. DRILL-2267.1.patch.txt
          3 kB
          Abdel Hakim Deneche

          Activity

            People

            • Assignee:
              sphillips Steven Phillips
              Reporter:
              inramana Ramana Inukonda Nagaraj
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              Dates

              • Created:
                Updated:
                Resolved: