Bug #14142 | Round | ||
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Submitted: | 19 Oct 2005 14:29 | Modified: | 20 Oct 2005 12:44 |
Reporter: | Sedat Onur Orakoglu | Email Updates: | |
Status: | Not a Bug | Impact on me: | |
Category: | MySQL Server | Severity: | S3 (Non-critical) |
Version: | 5.0.15-BK, 5.0.13-rc-nt-max | OS: | Linux (Linux, windows 2000 pro) |
Assigned to: | CPU Architecture: | Any |
[19 Oct 2005 14:29]
Sedat Onur Orakoglu
[19 Oct 2005 15:41]
Valeriy Kravchuk
Thank you for a problem report. I was able to repeat it on Linux with 5.0.15-BK (ChangeSet@1.2007.4.1, 2005-10-18 18:51:07-07:00, patg@krsna.patg.net), but with slightly different result (that is strange too): mysql> create table test (field1 double(15,2)); Query OK, 0 rows affected (0.00 sec) mysql> insert into test set field1=109.57; Query OK, 1 row affected (0.01 sec) mysql> select 109.57 as a1,109.57/2 as a2,truncate(109.57/2,3) as a3, -> round(truncate(109.57/2,3),2) as a4, -> field1 as b1, -> field1/2 as b2, -> truncate(field1/2,3) as b3, -> round(truncate(field1/2,3),2) as b4 -> from test; +--------+-----------+--------+-------+--------+-----------+--------+-------+ | a1 | a2 | a3 | a4 | b1 | b2 | b3 | b4 | +--------+-----------+--------+-------+--------+-----------+--------+-------+ | 109.57 | 54.785000 | 54.785 | 54.79 | 109.57 | 54.785000 | 54.784 | 54.78 | +--------+-----------+--------+-------+--------+-----------+--------+-------+ 1 row in set (0.00 sec) mysql> select version(); +-----------+ | version() | +-----------+ | 5.0.15 | +-----------+ 1 row in set (0.00 sec) In my case, the key difference is among a3 and b3 fields. Looks like I know the reason for the difference (109.57 is of type decimal really, and for it the precision is guaranteed, unlike double). But I want this to be checked and, if it is the intended behaviour, properly documented (in http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
[20 Oct 2005 12:44]
Sergei Golubchik
Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.mysql.com/documentation/ and the instructions on how to report a bug at http://bugs.mysql.com/how-to-report.php Additional info: See http://dev.mysql.com/doc/mysql/en/problems-with-float.html