ORA-01940: cannot DROP a user that is currently logged in

" ORA-01940: cannot DROP a user that is currently logged in "

ORA-01940

We were trying to drop a user ( schema ) in our local Oracle Database & we suddenly hit the ORA-01940 error.

We closed all the SQL Clients ( Oracle SQL Developer, SQL* Plus, TOAD ) that we were using, but still the error persisted. We were quite flummoxed - until, we googled and landed on this article from Burleson Consulting.

We followed the advice in the article & quitely killed the "stale" sessions. We could then drop the schema and recreate it.

I have always admired the articles from Burleson Consulting & found the explanation of the ORA-01940 error very informative.