Analyse the item by frequency(number of time item has been sold) with total quantity and amount month wise to know the fast moving items.
select t1.ItemCode,count(t1.itemcode) as Frequency,sum(t1.quantity) as Quantity,sum(t1.linetotal) as SalesAmount,MONTH(t0.DocDate) as nMonth,year(t0.docdate) as nYear
from OINV t0
inner join inv1 t1 on t0.DocEntry=t1.DocEntry
group by t1.ItemCode,MONTH(t0.DocDate),year(t0.docdate)
order by count(t1.itemcode) desc
Best Regards,
MS