Uploaded image for project: 'Spark'
  1. Spark
  2. SPARK-26706

Fix Cast$mayTruncate for bytes

    XMLWordPrintableJSON

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Blocker
    • Resolution: Resolved
    • Affects Version/s: 1.6.3, 2.0.2, 2.1.3, 2.2.3, 2.3.2, 2.4.0
    • Fix Version/s: 2.3.3, 2.4.1
    • Component/s: SQL
    • Labels:

      Description

      The logic in Cast$mayTruncate is broken for bytes.

      Right now, mayTruncate(ByteType, LongType) returns false while mayTruncate(ShortType, LongType) returns true. Consequently, spark.range(1, 3).as[Byte] and spark.range(1, 3).as[Short] will behave differently.

      Potentially, this bug can lead to silently corrupting someone's data.

      // executes silently even though Long is converted into Byte
      spark.range(Long.MaxValue - 10, Long.MaxValue).as[Byte]
        .map(b => b - 1)
        .show()
      +-----+
      |value|
      +-----+
      |  -12|
      |  -11|
      |  -10|
      |   -9|
      |   -8|
      |   -7|
      |   -6|
      |   -5|
      |   -4|
      |   -3|
      +-----+
      // throws an AnalysisException: Cannot up cast `id` from bigint to smallint as it may truncate
      spark.range(Long.MaxValue - 10, Long.MaxValue).as[Short]
        .map(s => s - 1)
        .show()
      

        Attachments

          Issue Links

            Activity

              People

              • Assignee:
                aokolnychyi Anton Okolnychyi
                Reporter:
                aokolnychyi Anton Okolnychyi
              • Votes:
                0 Vote for this issue
                Watchers:
                3 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: