Derby incorrectly rounds double values down during insert into NUMERIC
----------------------------------------------------------------------
Key: DERBY-123
URL: http://issues.apache.org/jira/browse/DERBY-123
Project: Derby
Type: Bug
Components: SQL
Versions: 10.0.2.1
Environment: Linux JDK 1.4.2
Reporter: Geoff Soutter
When inserting a double value into a field defined as NUMERIC(a,b) using PreparedStatement.setDouble(),
Derby may incorrectly round the number down.
For example, a NUMERIC(5,2) field with a double = 4.64 ends up with a value of 4.63 in the
database. This works fine in Oracle and other databases.
The problem occurs because double cannot represent 4.64 exactly, so the actual value is 4.6399999...
SQLDecimal.setCoreValue uses BigDecimal(double) which constructs a BigDecimal of 4.6399999...
and then SQLDecimal.setWidth uses value.setScale(desiredScale, BigDecimal.ROUND_DOWN); Note
that BigDecimal javadoc recommends that the double constructor be avoided for this reason.
One fix appears to be to change SQLDecimal.setCoreValue(double) to avoid using the double
constructor of BigDecimal. Using Double.toString() and BigDecimal(String) looks as if it would
work as expected, because Double.toString() has "special rounding abilities" and converts
4.639999... back to 4.64.
--
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
http://issues.apache.org/jira/secure/Administrators.jspa
-
If you want more information on JIRA, or have a bug to report see:
http://www.atlassian.com/software/jira
|