The latest example uses SQL queries materials purchase price

This example can look up material from a SQL Server database in the latest purchase date of the minimum purchase price, that is, if the same material there are multiple procurement records, first of all take the maximum purchase date, if the same purchase date there are still many records, take the purchase price of the lowest of. (By Order By adjusting the other requirements can be achieved, for example, take the earliest recorded date or maximum purchase price)

--创建临时表，插入测试数据
if Object_id('Tempdb..#temp1') is not null drop table #temp1
create table #temp1(ItemNumber varchar(10),PurchDate date,PurchPrice decimal(10,2))
insert into #temp1(ItemNumber,PurchDate,PurchPrice)
select 'Item01', '2016-1-8',3.33 union all
select 'Item01', '2016-5-8',2.22 union all
select 'Item01', '2016-3-8',1.11 union all
select 'Item02', '2016-3-9',4.44 union all
select 'Item02', '2016-5-9',5.55 union all
select 'Item02', '2016-1-9',6.66 union all
select 'Item03', '2016-1-7',9.99 union all
select 'Item03', '2016-3-7',8.88 union all
select 'Item03', '2016-3-7',7.77
 
--查询所有信息
select * from #temp1 order by ItemNumber asc,PurchDate desc,PurchPrice asc
 
--使用row_number() over partition by 查询物料的最新采购价格，如果同一日期有多个价格取最小值
select *
from (
    select ItemNumber,PurchDate,PurchPrice,
    row_number() over(partition by ItemNumber order by ItemNumber asc,PurchDate desc,PurchPrice asc) row_num
    from #temp1) t1
where t1.row_num=1