I created a report with Jaspersoft Studio 6.2.0. The data for the report comes from an Oracle database. The report works fine as long as I compile it and as long as I only preview the result. But if I use the 'Database and Query Dialog' and want to use the 'Data preview' it only works for reports without grouping!! So if I use a grouping in my report the 'Data preview' shows me the exception message 'Reset group "Group1" not found for variable'. "Group1" is the name of my created group. (see attached file)
Why do I get this exception?
I use Java (jdk1.8.0_65/ jre1.8.0_65) and the oracle database 18.104.22.168.0.