Uploaded image for project: 'Spark'
  1. Spark
  2. SPARK-31404 file source backward compatibility after calendar switch
  3. SPARK-31662

Reading wrong dates from dictionary encoded columns in Parquet files

    XMLWordPrintableJSON

    Details

    • Type: Sub-task
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 3.0.0, 3.1.0
    • Fix Version/s: 3.0.0
    • Component/s: SQL
    • Labels:
      None

      Description

      Write dates with dictionary encoding enabled to parquet files:

      Welcome to
            ____              __
           / __/__  ___ _____/ /__
          _\ \/ _ \/ _ `/ __/  '_/
         /___/ .__/\_,_/_/ /_/\_\   version 3.1.0-SNAPSHOT
            /_/
      
      Using Scala version 2.12.10 (OpenJDK 64-Bit Server VM, Java 1.8.0_242)
      Type in expressions to have them evaluated.
      Type :help for more information.
      
      scala> spark.conf.set("spark.sql.legacy.parquet.rebaseDateTimeInWrite.enabled", true)
      
      scala> :paste
      // Entering paste mode (ctrl-D to finish)
      
                Seq.tabulate(8)(_ => "1001-01-01").toDF("dateS")
                  .select($"dateS".cast("date").as("date"))
                  .repartition(1)
                  .write
                  .option("parquet.enable.dictionary", true)
                  .mode("overwrite")
                  .parquet("/Users/maximgekk/tmp/parquet-date-dict")
      
      // Exiting paste mode, now interpreting.
      

      Read them back:

      scala> spark.read.parquet("/Users/maximgekk/tmp/parquet-date-dict").show(false)
      +----------+
      |date      |
      +----------+
      |1001-01-07|
      |1001-01-07|
      |1001-01-07|
      |1001-01-07|
      |1001-01-07|
      |1001-01-07|
      |1001-01-07|
      |1001-01-07|
      +----------+
      

      Expected values must be 1000-01-01.

      I checked that the date column is encoded by dictionary via:

      ➜  parquet-date-dict java -jar ~/Downloads/parquet-tools-1.12.0.jar dump ./part-00000-84a77214-0c8c-45e9-ac41-5ca863b9dd94-c000.snappy.parquet
      row group 0
      --------------------------------------------------------------------------------
      date:  INT32 SNAPPY DO:0 FPO:4 SZ:74/70/0.95 VC:8 ENC:BIT_PACKED,RLE,P [more]...
          date TV=8 RL=0 DL=1 DS: 1 DE:PLAIN_DICTIONARY
          ----------------------------------------------------------------------------
          page 0:                  DLE:RLE RLE:BIT_PACKED VLE:PLAIN_DICTIONARY [more]... VC:8
      INT32 date
      --------------------------------------------------------------------------------
      *** row group 1 of 1, values 1 to 8 ***
      value 1: R:0 D:1 V:1001-01-07
      value 2: R:0 D:1 V:1001-01-07
      value 3: R:0 D:1 V:1001-01-07
      value 4: R:0 D:1 V:1001-01-07
      value 5: R:0 D:1 V:1001-01-07
      value 6: R:0 D:1 V:1001-01-07
      value 7: R:0 D:1 V:1001-01-07
      value 8: R:0 D:1 V:1001-01-07
      

        Attachments

          Issue Links

            Activity

              People

              • Assignee:
                maxgekk Maxim Gekk
                Reporter:
                maxgekk Maxim Gekk
              • Votes:
                0 Vote for this issue
                Watchers:
                3 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: