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CREATE TABLE [TEST] (
[nn] [varchar] (50) COLLATE Chinese_PRC_CI_AS NOT NULL ,
CONSTRAINT [PK_TEST] PRIMARY KEY CLUSTERED
(
[nn]
) ON [PRIMARY]
) ON [PRIMARY]
GO

select * from TEST

insert into TEST(nn)
values(N'BSS?¨º?¡ìID')

insert into TEST(nn)
values(N'BSS¡ìID')
/**//*
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Óï¾äÒÑÖÕÖ¹¡£

*/

declare @s nvarchar(50)
,@s2 nvarchar(50)

select @s =N'BSS?¨º?¡ìID' , @s2 = N'BSS¡ìID'

select 1 where @s=@s2

select 1 where N'BSS?¨º?¡ìID'=N'BSS¡ìID'
/**//*

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*/

declare @s varchar(50)
,@s2 varchar(50)

select @s =N'BSS?¨º?¡ìID' , @s2 = N'BSS¡ìID'

select 1 where @s=@s2

select 1 where N'BSS?¨º?¡ìID'=N'BSS¡ìID'
/**//*

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*/

תÔØÓÚ:https://www.cnblogs.com/evlon/archive/2006/05/25/409049.html