sql求助，找出同一单位日期最大的一条记录,且单位只能出一次

[xwt799023]

dwid data money
1 2013/5/26 23000.00
2 2013/5/3 23000.00
2 2013/5/1 22.00
3 2013/5/14 23000.00
3 2013/5/1 22.00
4 2013/5/1 30000.00

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要求出来的结果为

dwid data money
1 2013/5/26 23000.00
2 2013/5/3 23000.00
3 2013/5/14 23000.00
4 2013/5/1 30000.00

[u010412956]

select dwid,data,money from (select t.* ,row_number() over(partition by dwid order by data desc) rn from t ) where rn=1

[小海葵1]

select dwid, dd, money from (select row_number() over(partition by dd order by money desc) as rn, dwid, dd, money from test) where rn = 1

[NIan_jun]

with t as
(
select 1 dwid,to_date('2013/5/26','YYYY/MM/DD') date1,23000 money from dual
union all
select 2 dwid,to_date('2013/5/3','YYYY/MM/DD') m,23000 s from dual
union all
select 2 dwid,to_date('2013/5/3','YYYY/MM/DD') m,230000 s from dual
union all
select 2 dwid,to_date('2013/5/1','YYYY/MM/DD') m,22 s from dual
union all
select 3 dwid,to_date('2013/5/14','YYYY/MM/DD') m,23000 s from dual
union all
select 3 dwid,to_date('2013/5/1','YYYY/MM/DD') m,22 s from dual
union all
select 4 dwid,to_date('2013/5/1','YYYY/MM/DD') m,30000 s from dual
)
select dwid,date1,money from (
select dwid,date1,money,row_number()over(partition by dwid order by date1 desc,money desc) rn from t 
) where rn=1

如果存在相同日期取money 最大的记录

[善若止水]

一 子查询依据每个单位查出来最大的data 二 依据子查询的结果查出来所要的数据

[cutebear2008]

select t1.* from table_name t1 where not exists (select 1 from table_name t2 where t1.dwid = t2.dwid and t2.date > t1.date);

[sych888]

select * from tab_name where (dwid,data) in (select dwid,max(data) from tab_name group by dwid);