这个SQL如何写

[yousite1]

有合同明细表，结构如下：
GoodsNO 商品编号
GoodsName 商品名称
Brand 品牌
Marque 商品型号
AgreementCode 合同编号
BegDate 合同生效日期
EndDate 合同失效日期
SignDate 签约日期
Signer 签合同人
LastUpdate 最后更改时间

我想实现读出合同单号列表，每个合同对应多条商品信息，我想实现只不重复的读出合同号，并且按最后更改时间排序
发现这样写　SELECT DISTINCT AgreementCode FROM Mall_StoreGoods Order by LastUpdate　desc会
出错，请帮我看一下要怎么写这个SQL才好

[-狙击手-]

SELECT DISTINCT AgreementCode FROM Mall_StoreGoods Order by LastUpdate　desc


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语法上没有错呀，

[kk19840210]

select AgreementCode ,LastUpdate=max(LastUpdate) from Mall_StoreGoods group by AgreementCode order by max(LastUpdate) desc

[dawugui]

select a.* from tb a where 最后更改时间 = (select max(最后更改时间) from tb where 合同编号 = a.合同编号) order by a.最后更改时间 desc

[-狙击手-]

select *
from Mall_StoreGoods a
where not exists(select 1 from Mall_StoreGoods where AgreementCode = a.AgreementCode and LastUpdate > a.LastUpdate)

[dawugui]

select a.* from tb a where LastUpdate = (select max(LastUpdate) from tb where AgreementCode = a.AgreementCode) order by a.LastUpdate desc