How to deregister a database from a Recovery Catalog

Log on to the target database:

SQL*Plus: Release 11.2.0.2.0 Production on Tue Jan 28 14:00:50 2014

Copyright (c) 1982, 2010, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, Oracle Label Security,
OLAP, Data Mining, Oracle Database Vault and Real Application Testing options

SQL> select dbid,name from v$database;

      DBID NAME
---------- ---------
 305453026 PRODDB01

connect to the recovery catalog through sqlplus:

sqlplus uid/pwd@RMANCAT

SQL*Plus: Release 11.2.0.2.0 Production on Tue Jan 28 14:01:33 2014

Copyright (c) 1982, 2010, Oracle.  All rights reserved.

Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining
and Real Application Testing options

SQL> select db_key,dbid,name from rc_database
  2  where dbid=305453026;

    DB_KEY       DBID NAME
---------- ---------- --------
         1  305453026 PRODDB01

Finally, execute the procedure dbms_rcvcat.unregisterdatabase, passing in the parameters db_key and dbid:

SQL> execute dbms_rcvcat.unregisterdatabase(1,305453026);

PL/SQL procedure successfully completed.