Use (not long) number for encoding time in multiple column key
Use (not long) number for encoding time in multiple column key

Because time is not long number. (3 byte integer)

naoa/mroonga,yoku0825/mroonga,naoa/mroonga,yoku0825/mroonga,naoa/mroonga,mroonga/mroonga,mroonga/mroonga,yoku0825/mroonga,naoa/mroonga,yoku0825/mroonga,yoku0825/mroonga,mroonga/mroonga,naoa/mroonga,yoku0825/mroonga,mroonga/mroonga,naoa/mroonga