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  1. Hive
  2. HIVE-17030

HPL/SQL: Many cast operations are ignored without warning or notice.

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    Details

    • Type: Bug
    • Status: Patch Available
    • Priority: Critical
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: hpl/sql
    • Labels:
      None

      Description

      This bug is part of a series of issues and surprising behavior I encountered writing a reporting script that would aggregate values and give rows different classifications based on an the aggregate. Addressing some or all of these issues would make HPL/SQL more accessible to newcomers.

      Consider this code:

        val1d := cast('10.0' as double);
        val2d := cast('5.0' as double);
        declare val1i int = 5;
        declare val2i int = 5;
        val1i = val1d;
        diff := val1i - val2i;
      

      What is the value of diff? You might think it is 5 but in fact it is 0. Why? Because when you attempt to assign val1i to val1d, this code in Var.java is executed:

          else if (type == Type.BIGINT) {
            if (val.type == Type.STRING) {
              value = Long.parseLong((String)val.value);
            }
          }
          else if (type == Type.DECIMAL) {
      

      Since there is no case for assigning a double to a bigint, the expression is essentially ignored and the value remains the same. This behavior leads to many surprising results.

      It would be best if HPL/SQL could re-use the cast code from Hive since there are a lot of cases to consider.

      Version = 3.0.0-SNAPSHOT r71f52d8ad512904b3f2c4f04fe39a33f2834f1f2

        Attachments

        1. HIVE-17030.1.patch
          5 kB
          Dmitry Tolpeko

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            People

            • Assignee:
              dmtolpeko Dmitry Tolpeko
              Reporter:
              cartershanklin Carter Shanklin
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              Dates

              • Created:
                Updated: