Reverse Product Lineage :Compare Each Product Sold with the One Before It in the Same Category Intermediate

          select o.orderdate,
       p.category,
       p.name as productname,
       lag(p.name) over (partition by p.category
                         order by o.orderdate asc) as previousproduct
from orderdetails od
join orders o on od.orderid = o.orderid
join products p on od.productid = p.productid
where o.status = 'Completed'
  and o.orderdate between '2245-08-01' and '2245-08-31';