All oracle queries, tablespaces, and their relationships

All oracle queries, tablespaces, and their relationships

Select * from dba_users; view all users in the database, provided that you have the dba permission account, such as sys, system
Select * from all_users; view all users you can manage
Select * from user_users; view current user information

Query the user's tablespace:

Select username, default_tablespace from dba_users; query the tablespace where all users in the database are located

Select username, default_tablespace from user_users; tablespace of the current user in the production line

Query the names of all tablespaces:

Select tablespace_name from dba_tablespaces;