Follow below steps for deinstalling XDB component:

--- The catnoqm.sql script drops XDB.
>SQL> spool xdb_removal.log
SQL> set echo on;
SQL> connect / as sysdba
SQL> shutdown immediate;
SQL> startup
SQL> @?/rdbms/admin/catnoqm.sql
SQL> spool off;

FOR INSTALLING XDB COMPONENT:

----The catqm.sql script requires few parameters be passed to it when run:

SQL> spool xdb_install.log
SQL> set echo on;
SQL> connect / as sysdba
SQL> shutdown immediate;
SQL> startup;
-----SQL> @?/rdbms/admin/catqm.sql <XDB pwd> <XDB default tbs> <XDB temporary tbs> <SecureFiles = YES/NO>   
SQL> @?/rdbms/admin/catqm.sql test#1235 USERS TEMP YES
SQL> @?/rdbms/admin/utlrp.sql
SQL> spool off

 SecureFiles = YES or NO
(If YES is specified, the XDB repository will use SecureFile storage.
If NO is specified, LOBS will be used.
To use SecureFiles, compatibility must be set to 11.2.
The tablespace specified for the XDB repository must be using
Automatic Segment Space Management (ASSM) for SecureFiles to be used.)