This is an odd situation, most people are probably struggling more with getting REST to work than to get installed APEX to come up with the login.

I encountered an odd situation recently where REST worked, SQL Developer Web worked but APEX did not. Many attempts to install and uninstall ORDS and we were still at the same situation. The error message we got was along the lines of “connection pool is a template pool”.

Eventually I noticed that the setting for proxied in the pool was disabled. How odd, we did request it in our command. It turns out this happens if you install ORDS in a CDB but there is no APEX in the PDB$SEED. There is even a pretty explicit comment about it high up in the output from the install.

So we have a situation where we installed ORDS in CDB with pluggable mapping of the PDBS. APEX is just installed in the PDBS. Not in PDB$SEED and not in the CDB. So how does one fix it? It turns out just changing the setting back to proxied is enough. You can do it with the ORDS config command.

You may see some Java stacktraces in your log. For us they only occured in a pretty specific case. Either way it does not hurt anything other than that the user gets en error for the slightly invalid request they made.

I may get around to write a few words about our observations on that too.