select owm=isnull(b.owm,'')
,a.owldm,a.omc,a.num1,a.num2
from v_table1 a
left join(
select owm,owldm=min(owldm)
from v_table1
group by owm
)b on a.owm=b.owm and a.owldm=b.owldm
,a.owldm,a.omc,a.num1,a.num2
from v_table1 a
left join(
select owm,owldm=min(owldm)
from v_table1
group by owm
)b on a.owm=b.owm and a.owldm=b.owldm
create table v_table1(owm varchar(10),owldm varchar(10),omc varchar(10),num1 int,num2 int)
insert v_table1 select '204',' P01','零件1',100,0
union all select '204',' P02','零件2',200,0
union all select '204',' P03','零件3',100,0
union all select '205',' P05','零件5',200,0
union all select '205',' P06','零件6',200,0
go--查询
select owm=isnull(b.owm,'')
,a.owldm,a.omc,a.num1,a.num2
from v_table1 a
left join(
select owm,owldm=min(owldm)
from v_table1
group by owm
)b on a.owm=b.owm and a.owldm=b.owldm
go--删除测试
drop table v_table1/*--测试结果owm owldm omc num1 num2
---------- ---------- ---------- ----------- -----------
204 P01 零件1 100 0
P02 零件2 200 0
P03 零件3 100 0
205 P05 零件5 200 0
P06 零件6 200 0(所影响的行数为 5 行)
--*/