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  1. MariaDB Server
  2. MDEV-6853

Unexpected zero result on 1 % <very small decimal> (wrong default precision of the returned result?)

Details

    • Bug
    • Status: Open (View Workflow)
    • Minor
    • Resolution: Unresolved
    • 5.5.40
    • 5.5(EOL)
    • None
    • None

    Description

      MariaDB [test]> select 1 % 0.00000000000000000000000000000032349 ;
      		 
      +-------------------------------------------+
      		 
      | 1 % 0.00000000000000000000000000000032349 |
      		 
      +-------------------------------------------+
      		 
      |          0.000000000000000000000000000000 |
      		 
      +-------------------------------------------+
      		 
      1 row in set (0.00 sec)

      Technically, the second operand is outside DECIMAL precision (it has 30 zeros after the point), so it wouldn't be strange if the query considered it 0 and produced 0. But the current result is difficult to explain.

      MySQL 5.5 and PostgreSQL return a non-zero value:

      postgres=# select 1 % 0.00000000000000000000000000000032349 ;
      		 
                     ?column?                
      ---------------------------------------
      		 
       0.00000000000000000000000000000018574
      		 

      MySQL [test]> select 1 % 0.00000000000000000000000000000032349 ;
      		 
      +-------------------------------------------+
      		 
      | 1 % 0.00000000000000000000000000000032349 |
      		 
      +-------------------------------------------+
      		 
      |     0.00000000000000000000000000000018574 |
      		 
      +-------------------------------------------+
      		 
      1 row in set (0.00 sec)

      Attachments

        Issue Links

          relates to

          Task - A task that needs to be done. MDEV-6841 test decimal math

          • Major - Major loss of function.
          • Open

          Activity

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              serg Sergei Golubchik
              elenst Elena Stepanova
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              Dates

                Created:
                Updated:

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