Activate Standby Database on Oracle 11g

On Oracle 11g to activate standby database we should do:

--stop apply process  
 SQL> alter database recover managed standby database cancel;  
 --finish recovery managed  
 SQL> alter database recover managed standby database finish;  
 Database altered.  
 --activate database  
 SQL> alter database activate physical standby database;  
 Database altered.  
 --open database  
 SQL> alter database open;  
 Database altered.  
 SQL> select name, open_mode from v$database;  
 NAME   OPEN_MODE  
 --------- --------------------  
 PROD1   READ WRITE  
 SQL>