Convert Physical Standby to Snapshot Standby and Vice-versa - Quick commands

Converting Physical Standby to Snapshot Standby

1. Check Flashback is enabled. Not mandatory
• select DB_UNIQUE_NAME, OPEN_MODE, DATABASE_ROLE,flashback_on from v$database;
2. Set Recovery dest and dest size
• Show parameter db_recovery_file_dest
3. Stop Redo Apply
• ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
4. For RAC - Mount only one instance
• srvctl stop database -d <database name>
• srvctl start instance -d <databasename> -i <instancename> -o mount
5. At DGMGRL prompt - 
• CONVERT DATABASE <standby database> TO SNAPSHOT STANDBY
6. Restart the Database
• srvctl stop database -d <database name>
• srvctl start database -d <database name>
7. Check Database role
• select DB_UNIQUE_NAME, OPEN_MODE, DATABASE_ROLE,flashback_on from v$database;    

Converting Snapshot Standby to Physical Standby

1. Check Database role
• select DB_UNIQUE_NAME, OPEN_MODE, DATABASE_ROLE,flashback_on from v$database;
2. Check restore point
• select name, guarantee_flashback_database from v$restore_point;
3. For RAC - Mount only one instance
• srvctl stop database -d <database name>
• srvctl start instance -d <databasename> -i <instancename> -o mount
4. At DGMGRL prompt - 
• CONVERT DATABASE <standby database> TO PHYSICAL STANDBY
5. Restart the Database
• srvctl stop database -d <database name>
• srvctl start database -d <database name>
6. Check Database role
• select DB_UNIQUE_NAME, OPEN_MODE, DATABASE_ROLE,flashback_on from v$database;
7. Start the MRP on Standby
• ALTER DATABASE RECOVER MANAGED STANDBY DATABASE NODELAY USING CURRENT LOGFILE DISCONNECT FROM SESSION;