When users try to run big queries in Oracle Discoverer, they receive an ‘Out of memory’ error. In the Java console you will see an error:
‘Exception occurred during event dispatching: java.lang.OutOfMemoryError: Java heap space’.
These errors are very clear and such an error indicates the application does not have enough memory assigned even if your machine has loads of memory. By default Java assigns 64 MB. Therefore you have to increase the assigned memory.