Question

假设有一个字符串 M004US8060UfG 如果前四个字符 M004 ，那么我必须删除 M004 并保留US8060UfG 如果最后一个字符为零，即 M004US8060Uf0 ，则删除最后一个零，仅保留 US8060Uf

Answer 1

尝试这样

DECLARE @t TABLE(s VARCHAR(100))
INSERT INTO @t VALUES('M004US8060UfG'),('M004US8060Uf0'),('SomeOther')

SELECT Step2
FROM @t AS t
CROSS APPLY(SELECT CASE WHEN LEFT(t.s,4)='M004' THEN SUBSTRING(t.s,5,9999) ELSE t.s END AS Step1 ) AS A
CROSS APPLY(SELECT CASE WHEN RIGHT(Step1,1)='0' THEN LEFT(Step1,LEN(Step1)-1) ELSE Step1 END AS Step2) AS B

结果

US8060UfG
US8060Uf
SomeOther

Answer 2

也许一个简单的案例（偷走Shnugo的桌子）

注意：这假定只删除一个尾随零

DECLARE @t TABLE(s VARCHAR(100))
INSERT INTO @t VALUES('M004US8060UfG'),('M004US8060Uf0'),('SomeOther'),('Trailing0')

Select *
      ,NewValue = case when S like 'M004%0' then substring(S,5,len(S)-5) 
                       when S like 'M004%'  then substring(S,5,len(S)) 
                       when S like '%0'     then substring(S,1,len(S)-1)
                       else S end
 From  @t

<强>返回

s               NewValue
--------------  -----------
M004US8060UfG   US8060UfG
M004US8060Uf0   US8060Uf
SomeOther       SomeOther
Trailing0       Trailing

特定条件下的字符串删除和保留

2 个答案: