I just started learning SQL and Databases using Oracle Database 11g XE. I noticed that under the Application Builder section there is always a Sample Application, which application_ID is 100 for the first workspace. When I create a new workspace, the ID of this sample application in the new workspace increases accordingly, so for my second workspace it's 101, and so on. But if I delete a workspace, without first deleting it's application, the id for new applications still increases, which leads me to think that the application is still there somewhere even after I deleted the workspace and dropped the user... They don't show up anywhere, not even in the admin view... How can I find and delete these sample applications that no longer belong to any workspace? Thank you
Note: If I delete the sample application before deleting the workspace, then the next new workspace will have the same ID for the sample application, so that's why I believe these applications are still there somewhere undeleted when I don't delete the application before deleting the workspace.
As far as I can tell, once you drop the workspace, all its applications (and everything else - shared components etc.) are dropped with it. The fact that Sample Application ID keeps increasing - in my opinion - depends on some internal mechanism which uses some kind of a "smart counter" / "sequence", i.e. if you delete an application it decreases, but - if you delete a workspace, it does not. Please, note that this is just my opinion, I don't know how it exactly works.
Anyway: to check applications you currently have, connect as a privileged user (such as SYS). First, check what Apex users you have:
SQL> select * From all_users where username like 'APEX%' order by username;
USERNAME USER_ID CREATED
------------------------------ ---------- --------
APEX_INSTANCE_ADMIN_USER 156 01.06.17
APEX_LISTENER 173 05.03.19
APEX_PUBLIC_USER 86 10.10.16
APEX_REST_PUBLIC_USER 174 05.03.19
APEX_050000 87 10.10.16
APEX_050100 154 01.06.17
APEX_180200 178 08.03.19
7 rows selected.
SQL>
Then find applications within certain Apex user; as you're on 11g XE and if you didn't upgrade Apex, I believe you have APEX_040000 (which is built-in into 11g XE). I don't have it, but I do have other versions, so:
SQL> select workspace, application_id, application_name, owner
2 from apex_050100.apex_applications
3 order by application_id;
WORKSPACE APPLICATION_ID APPLICATION_NAME OWNER
--------------- -------------- ------------------------------ ---------------
RNAL 100 Sample Database Application RNAL
WEB 101 Sample Database Application WEB
RNAL 129 Warehouse RNAL
MBUN 130 web_service MBUN
ORAGIS 131 GIS ORAGIS
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