Double add double get wrong result

[yangjiajun]

Hello.I do simple add operation but get wrong result.

Here is a reproduce step:

CREATE TABLE PUBLIC.TEST (
        A DOUBLE,
        B DOUBLE,
        K VARCHAR,
        CONSTRAINT K PRIMARY KEY (K)
);

INSERT INTO test(A,B,K)values(-11674.46,11674.67,'1')

SELECT to_char(A+B) FROM test

The result:.21000000000094587.But it obviously should be .21.

Do u have any ideas about this?



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Sent from: http://apache-ignite-users.70518.x6.nabble.com/

[ptupitsyn]

Hello,

You'll get the same results in plain Java code

      double x = -11674.46;
      double y = 11674.67;
      System.out.println(x + y);

This is caused by the internal floating point representation [1] [2]

You can try DECIMAL instead of DOUBLE.

[1] https://stackoverflow.com/questions/322749/retain-precision-with-double-in-java

[2] https://en.wikipedia.org/wiki/Floating-point_arithmetic

On Tue, Jan 12, 2021 at 5:46 AM yangjiajun <[hidden email]> wrote:

Hello.I do simple add operation but get wrong result.

Here is a reproduce step:

CREATE TABLE PUBLIC.TEST (
        A DOUBLE,
        B DOUBLE,
        K VARCHAR,
        CONSTRAINT K PRIMARY KEY (K)
);

INSERT INTO test(A,B,K)values(-11674.46,11674.67,'1')

SELECT to_char(A+B) FROM test

The result:.21000000000094587.But it obviously should be .21.

Do u have any ideas about this?



--
Sent from: http://apache-ignite-users.70518.x6.nabble.com/