如何从列中检索 HTML 标记

Question

我有一个 SQL 表，其中有一列包含一些 HTML/XML 标记。这是一个例子：

<root><Physicians><name>John Helsinki, MD</name>
<picture><img src="/uploadedImages/svr/physicians/images/John web.jpg?n=9059" alt="Helsinki, John Photo" /></picture>
<gender>M</gender>
<specialty><a href="/WA/test.aspx?56" title="Eye Care">OPT</a></specialty>
<specialty2></specialty2>
<specialty3></specialty3>
<additional_specialty></additional_specialty>
</Physicians>
</root>

如何提取位于<picture></picture> 之间的<img> 标记？

我知道我可以在 SQL 中使用 LIKE 关键字，但我不确定如何继续...

Answer 1

您可以使用 XPath 来利用列类型 - XML

declare @thing XML
set @thing = '<root><Physicians><name>John Helsinki, MD</name>
<picture><img src="/uploadedImages/svr/physicians/images/John web.jpg?n=9059" alt="Helsinki, John Photo" /></picture>
<gender>M</gender>
<specialty><a href="/WA/test.aspx?56" title="Eye Care">OPT</a></specialty>
<specialty2></specialty2>
<specialty3></specialty3>
<additional_specialty></additional_specialty>
</Physicians>
</root>'

SELECT @thing.query('/root/Physicians/picture/img')

另一种通过表格完成的方法：

DECLARE @XmlTable TABLE (ID INT NOT NULL, XmlData XML)
INSERT INTO @XmlTable 
        (ID, XmlData)
VALUES
        (1, '<root><Physicians><name>John Helsinki, MD</name>
<picture><img src="/uploadedImages/svr/physicians/images/John web.jpg?n=9059" alt="Helsinki, John Photo" /></picture>
<gender>M</gender>
<specialty><a href="/WA/test.aspx?56" title="Eye Care">OPT</a></specialty>
<specialty2></specialty2>
<specialty3></specialty3>
<additional_specialty></additional_specialty>
</Physicians>
</root>')

select XmlData.query('/root/Physicians/picture/img') from @XmlTable

这利用了任何 XML 变量类型上可用的query method，因此在此上下文中：

select [column].query('/root/Physicians/picture/img') from [table]