What don't you understand? In the post I showed the player with steam ID STEAM_0:1:12345 has items 1, 2, 3 and 5 at the same time (until get_systime( ) is higher than unixtime from the table)
Anyway, using numbered indexes for items is not the best idea because if the plugin order changes, items will also have different identifiers, so you should think about some sort of unique string identifiers.