The derby.stream.error.rollingFile.count property specifies the number of rolling log files to permit before deleting the oldest file when rolling to the next file, if derby.stream.error.style is set to rollingFile.
If derby.stream.error.style is not set, this property setting is ignored.
You can override other rolling log file defaults by setting derby.stream.error.rollingFile.limit or derby.stream.error.rollingFile.pattern.
derby.stream.error.rollingFile.count=count
The specified count value must be equal to or greater than 1.
10.
derby.stream.error.rollingFile.count=1
This property is static; if you change it while Derby is running, the change does not take effect until you reboot.