How To Convert a Standby database to a Standalone Database After removing it from Data guard environment

Scenario:

You have already removed your standby database from your data guard environment and now you want to converts it to a Standalone database.

Solution:

In your removed standby database:

SQL> select database_role from v$database;

DATABASE_ROLE

------------------------------------------------

PHYSICAL STANDBY

SQL> alter database activate standby database;

Database altered.

SQL> SHUTDOWN IMMEDIATE;

ORA-01109: database not open

Database dismounted.

ORACLE instance shut down.

SQL> select database_role from v$database;

DATABASE_ROLE

------------------------------------------------

PRIMARY

For more information please check Oracle Support Doc ID 2074686.1