Rolling forward the standby db using incremental backup

Hi Folks,

I'm trying to roll forward the standby database using incrementa backup and after catalog the backup set and try to recover using oracle recommended document, i get the following error:

RMAN> recover database noredo;

Starting recover at 15-AUG-16

using channel ORA_DISK_1

using channel ORA_DISK_2

using channel ORA_DISK_3

using channel ORA_DISK_4

using channel ORA_DISK_5

using channel ORA_DISK_6

using channel ORA_DISK_7

using channel ORA_DISK_8

RMAN-00571: ===========================================================

RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============

RMAN-00571: ===========================================================

RMAN-03002: failure of recover command at 08/15/2016 13:57:34

RMAN-06094: datafile 1 must be restored

Can you please assist on this? when we are rolling forward do we need to restore all datafiles? i dont see that within the recommended procedures