I started getting this error while opening the app
Application was working fine. All of a sudden this error came while opening the application.
" An Error Occurred While Processing This Page. Check The Log For Details. Please Close The Current Tab and Open Application Again."
I cannot see calc manger rules for this means in calc manager I am not able to see this app.
Also, in logs I see
java.lang.RuntimeException: Error loading objects from data source: java.sql.SQLSyntaxErrorException: ORA-00942: table or view does not exist
Validating the data source is sometimes a good way to find out if there is an issue, though this wouldn't help if the tables have been removed, sometimes it can be privileges have been changed for the account used in the data source, if the account was locked you should in theory get the following Oracle code ORA-28000
If it is not important then you can try deleting and recreating the application, if you want to be sure after you delete the application then drop/recreate the Oracle schema.
If you have problems deleting the application and have to remove it manually the following post might be helpful Planning 18.104.22.168 - Manually Delete a Classic Application
In Shared Services under your application groups you should see the planning apps, exactly where they are located depends on which group you registered them against, anyway if you wanted to delete you would just right click the application and delete.