Question

我有一个名为“project”的表，其列名为“path”，其XML数据存储为text（nvarchar（max））。

这是“path”列

下的其中一行的内容

<?xml version="1.0" encoding="utf-16"?>
<ProjectPerfoceSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<Server>101.0.101.101</Server>
<Port>1625</Port>
</ProjectPerfoceSetting>

我想得到以下输出，

服务器端口 101.0.101.101 1625

以下是我正在使用的查询，它返回null，

SELECT 
    CAST(path AS XML).value('declare namespace ns="http://www.w3.org/2001/XMLSchema";(/ProjectPerfoceSetting/Server/@Text)[1]', 'varchar(200)')
FROM project

有人可以建议上面的查询有什么问题。提前谢谢。

更新

不知何故，查询将为以下XML数据返回null，

<?xml version="1.0" encoding="utf-16"?>
<ProjectTFSSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://DT">
<Server>45.25.211.222</Server>
<Port>8080</Port>
</ProjectTFSSetting>

查询

Select A.[ProjectName]

      ,Server = B.XMLData.value('(ProjectTFSSetting/Server)[1]', 'varchar(200)')
      ,URL = B.XMLData.value('(ProjectTFSSetting/Url)[1]'  , 'varchar(200)')
 From [CxDB].[dbo].[Broadridge_Scans_View] A
 Cross Apply (Select XMLData = cast(Path as xml)) B

另外，列“路径”也存储了一些文本数据。除了解析XML数据之外，我该如何访问它们？

现在是另一种情况，

这就是表“项目”在下面的列中的样子。

ID路径

1 <?xml version="1.0" encoding="utf-16"?><ProjectPerfoceSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Server>101.0.101.101</Server><Port>1625</Port></ProjectPerfoceSetting>

2 <?xml version="1.0" encoding="utf-16"?><ProjectGITSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><URL>http://test.com</Server><folder>/customer</folder></ProjectPerfoceSetting>

3 <?xml version="1.0" encoding="utf-16"?><ProjectTFSSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://DT"><Server>45.25.211.222</Server><Port>8080</Port></ProjectTFSSetting> 4有些文字不是xml

是否有可能低于输出？

ID  Server                            Port
1   101.0.101.101                     1625
2   http://test.com                   /customer 
3   http://londbcntfs:8080/tfs/BCN/   8080
4   some text not xml

Answer 1

最好将XML数据存储为xml。但是，通过添加CROSS APPLY（OUTER APPLY以显示NULL），促进转换变得很小。

示例（添加第二行以说明）

Declare @Project table (ID int,Path nvarchar(max))
Insert Into @Project values
(1,'<ProjectPerfoceSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Server>101.0.101.101</Server><Port>1625</Port></ProjectPerfoceSetting>'),
(2,'<ProjectTFSSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://DT"><Server>http://londbcntfs:8080/tfs/BCN/</Server><Port>8080</Port></ProjectTFSSetting>')

Select A.ID
      ,Server = B.XMLData.value('(*/Server)[1]', 'varchar(200)')
      ,Port   = B.XMLData.value('(*/Port)[1]'  , 'varchar(200)')
 From @Project A
 Cross Apply (Select XMLData = cast(replace(Path,'xmlns="','dummy="') as xml)) B

<强>返回

ID  Server                            Port
1   101.0.101.101                     1625
2   http://londbcntfs:8080/tfs/BCN/   8080

Answer 2

提供的ID 2 XML不正确。

对OUTER APPLY和IsNull（）的小改动

您还需要学习如何更好地格式化问题。

Declare @Project table (ID int,Path nvarchar(max))
Insert Into @Project values
(1,'<?xml version="1.0" encoding="utf-16"?><ProjectPerfoceSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Server>101.0.101.101</Server><Port>1625</Port></ProjectPerfoceSetting>'),
(3,'<?xml version="1.0" encoding="utf-16"?><ProjectTFSSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://DT"><Server>45.25.211.222</Server><Port>8080</Port></ProjectTFSSetting>'),
(2,'<?xml version="1.0" encoding="utf-16"?><ProjectGITSetting xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><URL>http://test.com</URL><folder>customer</folder></ProjectGITSetting>'),
(4,'some text not xml')

Select A.ID
      ,Server = isnull(B.XMLData.value('(*/Server)[1]', 'varchar(200)'),isnull(B.XMLData.value('(*/URL)[1]', 'varchar(200)'),Path))
      ,Port   = isnull(B.XMLData.value('(*/Port)[1]'  , 'varchar(200)'),B.XMLData.value('(*/folder)[1]', 'varchar(200)'))
 From @Project A
 Outer Apply (Select XMLData = cast(replace(Path,'xmlns="','dummy="') as xml)) B

<强>返回

ID  Server  Port
1   101.0.101.101       1625
3   45.25.211.222       8080
2   http://test.com     customer
4   some text not xml   NULL

使用text数据类型读取存储在MSSQL 2014数据库中的XML

2 个答案: