SQL SERVER替換函數工作奇數

Question

爲什麼我只能得到一個結果？

select replace(N'2',N'2','X') as Text 
    union 
    select replace(N'2',N'²','X') as Text 

第二個SELECT語句包含一個平方。

@@版本=的Microsoft SQL Server 2012 - 11.0.5623.0

Answer 1

行爲取決於歸類的區分大小寫：

SELECT REPLACE(N'2' COLLATE Latin1_General_CS_AS, N'2' COLLATE Latin1_General_CS_AS,'X' COLLATE Latin1_General_CS_AS) as Text 
UNION 
SELECT REPLACE(N'2' COLLATE Latin1_General_CS_AS, N'²' COLLATE Latin1_General_CS_AS,'X' COLLATE Latin1_General_CS_AS) as Text 
GO 
--results: 
X 
2 
SELECT REPLACE(N'2' COLLATE Latin1_General_CI_AS, N'2' COLLATE Latin1_General_CI_AS,'X' COLLATE Latin1_General_CI_AS) as Text 
UNION 
SELECT REPLACE(N'2' COLLATE Latin1_General_CI_AS, N'²' COLLATE Latin1_General_CI_AS,'X' COLLATE Latin1_General_CI_AS) as Text 
GO 
--results: 
X 

當文字表述沒有指定整理，數據庫默認排序規則被使用。