Oracle Database ORA-01940: Unable to delete user currently connected

In Oracle database operations, there is a ORA-01940: Unable to delete the current connected user error, how to solve? This article introduces the solution, hoping to help you.
SQL> drop user a cascade;
Drop user a cascade
*
ERROR is located in row 1st:
ORA-01940: Unable to delete the currently connected user
Solution:
SQL> select username, sid, serial # from v $ session;
Username sid serial #
--------------------------------------------------
1 1
2 1
3 1
4 1
5 1
6 1
7 1
SYS 8 3
A 9 4
Nine rows have been selected.
SQL> alter system kill session '9, 4 ';
The system has been changed.
SQL> drop user a cascade; // Delete the user and all objects in the user tablespace
The user has been discarded.
About Oracle Database ORA-01940: Unable to delete the current connected user related knowledge is introduced here, I hope this introduction can be for you to gain something!

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