When querying a parallel table, processes are being left behind long after the query has executed.
In general, processes will not clear from the database until all the data has been fetched, or the cursor has been closed because another query has been executed, or the SQL tab has been closed, or the connection has closed or Toad is closed.
There are however a 3 scenarios where the parallel processes may not be released:
1. If you query a table in the editor using F9 (execute statement). If you don't fetch all the data and then go on to execute a script in the same tab using F5 (Execute as Script) then the processes will remain open until another F9 is executed in that tab. So, for example if a user queries a parallel table using F9 and then goes on to run a long running script (using F5), then the processes will remain open. If user leaves the script running overnight, for example, then the processes from the original F9 execution will still remain active until either another F9 execution is run, or the tab is closed, or the connection is closed or Toad is closed.
WORKAROUND
Ensure that all the data has been fetched, or run another query using the same execution type (i.e.If you ran the parallel table query with F9, then run another query with F9 in the same tab), or close the tab, connection or Toad.
STATUS
Scenario 1 - Use workaround
Scenario 2 & 3 - Waiting for fix in a future release of Toad for Oracle
