ORA-16087
        Switchover requires standby or current control file.
        
        
        Cause
        An attempt was made to perform a switchover operation using a backup or clone control file.
        Action
        Convert the backup control file into a current control file prior to attempting a switchover operation. A clone control file cannot be used for a switchover operation.
        
     
    
    
        ORA-16087
        Switchover requires standby or current control file.
        
        
        Cause
        An attempt was made to perform a switchover operation using a backup or clone control file.
        Action
        Convert the backup control file into a current control file prior to attempting a switchover operation. A clone control file cannot be used for a switchover operation.
        
     
    
    
        ORA-16087
        Switchover requires standby or current control file.
        
        
        Cause
        An attempt was made to perform a switchover operation using a backup or clone control file.
        Action
        Convert the backup control file into a current control file prior to attempting a switchover operation. A clone control file cannot be used for a switchover operation.