How to delete a user in Oracle 10 including all it's tablespace and datafiles

Question

When I give the command to drop a user i.e. DROP USER \'username\' cascade,

1. Does it deletes all the tablespace and datafiles used by that particular user.

Answer 1

After dropping the user, you need to, for each related tablespace, take it offline and drop it. For example if you had a user named 'SAMPLE' and two tablespaces called 'SAMPLE' and 'SAMPLE_INDEX', then you'd need to do the following:

DROP USER SAMPLE CASCADE;
ALTER TABLESPACE SAMPLE OFFLINE;
DROP TABLESPACE SAMPLE INCLUDING CONTENTS;
ALTER TABLESPACE SAMPLE_INDEX OFFLINE;
DROP TABLESPACE SAMPLE_INDEX INCLUDING CONTENTS;

Answer 2

DROP USER---->
DROP USER USER_NAME CASCADE;
DROP TABLESPACE---->
DROP TABLESPACE TABLESPACE_NAME INCLUDING CONTENTS AND DATAFILES;

Answer 3

You can check which table space is used by which user with the following query.

SELECT USERNAME, DEFAULT_TABLESPACE FROM DBA_USERS;

You can also see the list of table spaces by looking at the following tables

DBA_TABLESPACES
USER_TABLESPACES