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SQL code:
if object_id('[t_class]') is not null drop table [t_class]
go
create table [t_class]([classid] int,[classname] varchar(6))
insert [t_class]
select 100,'¼ÆÍø°à' union all
select 200,'µçḚ́à' union all
select 300,'Èí¼þ°à'
if object_id('[t_students]') is not null drop table [t_students]
go
create table [t_students]([studentsid] int,[classid] int,[fstudentsname] varchar(4))
insert [t_students]
select 1001,100,'Àîºì' union all
select 1002,100,'»ÆÃ÷' union all
select 2001,200,'ÖÜÌÎ' union all
select 2002,200,'ÈηÉ' union all
select 3001,300,'³Âº£' union all
select 3002,300,'ÁúÊË'

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select
classname=
case when
exists(
select 1
from (select a.*,b.classname from t_students a join t_class b on a.classid=b.classid) t2
where t2.classname=t1.classname and t2.studentsid<t1.studentsid)
then ''
else classname
end,
fstudentsname
from
(select a.*,b.classname from t_students a join t_class b on a.classid=b.classid) t


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select cast(convert(numeric(18,2),1275674000000/100000000)as real)
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sql ½ØÈ¡×Ö·û´®

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select
right(col,len(col)-charindex('|||',col)-2)
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SQLÈçºÎÓÅ»¯ÎÊÌâ - MS-SQL Server / ÒÉÄÑÎÊÌâ

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