Items last planned date query

Hello,

I have to find out the last date that each item set with MRP planning status was last planned. Does anyone have a query which might take into account pegging, supply, demand, the assembly/component relationship and the material demand histories on planned items? I've come up with various queries but due to my inexperience in this particular field of Oracle, i seem to be missing the mark on several items and am unsure which tables exactly i should be working with. I'm working in 11i and have factored in msc_full_pegging, msc_supplies, msc_demands, msc_system_items, mtl_sys_items_b, mtl_demand_histories. However i'm not sure if