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  1. Drools
  2. DROOLS-314

Build in accumulate functions are highly unreliable for long's and BigDecimals

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Details

    • Bug
    • Resolution: Duplicate
    • Critical
    • None
    • None
    • None
    • None

    Description

      When dealing with financial data, one should never ever use double's. Instead BigDecimal should be used.
      Not because BigDecimal is bigger (that's rarely a problem) but because it doesn't do any decimal to binary transformation.
      For example, it's impossible for a double to correctly represent "0.2", aka 1/5.
      Summing many doubles (or even a few differing in scale), can easily give wrong results (and for financial data this tends to be important).

      Using doubles to sum longs have the exact same problem.
      Attached is a testcase patch which proves this by checking if (MAX_LONG - 4L) and 3L sum up to be (MAX_LONG - 1L).
      Currently they don't.

      One possible way to solve this is to fix JBRULES-1075,
      which just happens to give drools-solver 3% more performance what a coincidence ^^

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        Issue Links

          duplicates

          Feature Request - Feature requests from customers and/or users DROOLS-1175 Accumulates: sum(Long), sum(BigDecimal), sum(Integer) and sum(BigInteger)

          • Major - To be worked after higher priority work items are addressed. When the severity is high and the effort to change it is low to moderate, this term is chosen. Issues in this category likely have an existing workaround but implementation or execution may be non-trivial.
          • Closed
          is related to

          Feature Request - Feature requests from customers and/or users DROOLS-315 Support overloading of accumulate functions: Add int (or long) based sum's, int based avarage's, etc

          • Critical - To be worked on immediately following BLOCKER issues.
          • Resolved

          Feature Request - Feature requests from customers and/or users JBRULES-1074 Support the use of Integer, Float, Short and Byte in accumulate functions

          • Minor - To be worked after urgent, high, and medium priorities are resolved. This term is chosen when the severity of the issue is low, or the complexity or effort to correct it may be higher, relatively speaking. For low priority issues, known workarounds exist or are not needed due to the trivial effort needed to address the issue.
          • Closed

          Bug - A problem that impairs or prevents the functions of the product. JBRULES-2749 Various rules stop firing when they are in unlucky packagename and there is a function declared and also a type declared

          • Major - To be worked after higher priority work items are addressed. When the severity is high and the effort to change it is low to moderate, this term is chosen. Issues in this category likely have an existing workaround but implementation or execution may be non-trivial.
          • Closed

          Activity

            People

              Unassigned Unassigned
              gdesmet@redhat.com Geoffrey De Smet (Inactive)
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              Dates

                Created:
                Updated:
                Resolved: