Either hiding or disabling these partitions are okay. My 2 partitions that I want to hide are /dev/sda1 and /dev/sda2 which are not declared in fstab file.
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc defaults 0 0
# / was on /dev/sda6 during installation
UUID=73b82a95-b080-4088-9c3d-1ff8445b2f68 / ext4 errors=remount-ro 0 1
# swap was on /dev/sda7 during installation
UUID=54330dab-8d32-4c99-a068-3bcb04f01b61 none swap sw 0 0