Question

我的select语句返回两列A列基于B列但是我删除了最初的17个字符。我想要做的是将A列中的所有字符都取出，直到它达到\（反斜杠）。任何人都可以帮助我实现这一目标 - 下面的当前代码

SELECT distinct substring(Path,17,18) AS Detail, Path
FROM [DB].[dbo].[Projects]
Where [Path] like '\DATA%'
AND [Deleted] = '0'

重新迭代，因为我的例子在下面的评论中不是很清楚。我试图从以下结果中提取

\DATA\More Data\Even More Data\Data 1

显示

Even More Data

所以我删除了前17个字符，直到下一个\

Answer 1

对于ColumnA，如果您只想取出前17个字符，则应使用

RIGHT(Path, LEN(Path) - 17)

如果Path超过35个字符，则当前解决方案将无法正常工作。

至于将字符串返回到第一个反斜杠，请使用：

SELECT LEFT(Detail, CHARINDEX('\', Detail)) FirstFolder, Detail, Path
FROM 
(
    SELECT distinct RIGHT(Path, LEN(Path) - 17) AS Detail, Path
    FROM [DB].[dbo].[Projects]
    Where [Path] like '\DATA%'
    AND [Deleted] = '0'
) a

或者一体化：

SELECT DISTINCT SUBSTRING(Path, 18, CHARINDEX('\', Path, 18) - 18) 
FROM [DB].[dbo].[Projects]
WHERE [Path] like '\DATA%'
AND [Deleted] = '0'

这说：

从path
从角色18开始
字符串的长度将通过从字符18，减去18开始查找path中第一个反斜杠的位置来计算（因为我们开始搜索第18个字符，我们希望它相对于我们的搜索开始不原始字符串的开头）

<强>更新

正如@etsa正确指出的那样，如果你不能保证Path长度至少为18个字符并且在每行 之后包含一个反斜杠 ，你应该使用以下内容仅返回符合此条件的行：

SELECT DISTINCT SUBSTRING(Path, 18, CHARINDEX('\', Path, 18) - 18) 
FROM [DB].[dbo].[Projects]
WHERE [Path] like '\DATA%'
AND [Deleted] = '0'
AND CHARINDEX('\', Path, 18) > 0

Answer 2

无论数据的长度如何，这都会获得您想要的父文件夹。

DECLARE @table TABLE ([Path] VARCHAR(256))
INSERT INTO @table VALUES
('\DATA\More Data\Even More Data\Data 1'),
('\\server\top folder\middle folder\bottom folder\file 1'),
('x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\this is what we want\x')

SELECT
    [Path]
    ,CHARINDEX('\',REVERSE([Path])) as [Reverse Position of last \]
    ,CHARINDEX('\',REVERSE([Path]),CHARINDEX('\',REVERSE([Path])) + 1) as [Reverse Postion of next to last \]
    ,REVERSE(
                SUBSTRING(
                    REVERSE([Path]),
                    CHARINDEX('\',REVERSE([Path]))+1,
                    CHARINDEX('\',REVERSE([Path]),CHARINDEX('\',reverse([Path]))+1)-CHARINDEX('\',REVERSE([Path])) - 1)) as [Your Desired Results]
FROM
    @table

<强>返回

+--------------------------------------------------------------+----------------------------+-----------------------------------+----------------------+
|                             Path                             | Reverse Position of last \ | Reverse Postion of next to last \ | Your Desired Results |
+--------------------------------------------------------------+----------------------------+-----------------------------------+----------------------+
| \DATA\More Data\Even More Data\Data 1                        |                          7 |                                22 | Even More Data       |
| \\server\top folder\middle folder\bottom folder\file 1       |                          7 |                                21 | bottom folder        |
| x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\x\this is what we want\x |                          2 |                                23 | this is what we want |
+--------------------------------------------------------------+----------------------------+-----------------------------------+----------------------+

左选择直到某个字符SQL

2 个答案: