如何从字符串中提取 html 结构?

How to extract html structure from string?

我有一篇很长的文字写在html :

<body>
    <h2>title 1</h2>
    <h2>This is an <b>important</b> title</h2>
        Some text
        <h3>This a subtitle b</h3>
        <h3>This is also <span style="font-weight:500">important</span></h3>        
</body>

我需要从中提取标题以创建 Table 内容。我希望结果为:

h2      Title 1
h2      This is an <b>important</b> title
h3      This a subtitle b
h3      This is also <span style="font-weight:500">important</span>

h2      Title 1
h2      This is an important title
h3      This a subtitle b
h3      This is also important

我试过了

select * from xmltable('body/*'  passing xmltype('<body><h2>title 1</h2><h2>This is an <b>important</b> title</h2>Some text<h3>This a subtitle b</h3><h3>This is also <span style="font-weight:500">important</span></h3></body>') 
columns 
tag_name varchar2(1000) path 'name()',
tag_value varchar2(1000) path 'text()')
where tag_name in ('h1','h2','h3','h4','h5')

但我收到错误消息:

ORA-19279: XPTY0004 - XQuery dynamic type mismatch: expected singleton sequence - got multi-item sequence
19279. 00000 -  "XPTY0004 - XQuery dynamic type mismatch: expected singleton sequence - got multi-item sequence" 
*Cause:    The XQuery sequence passed in had more than one item.
*Action:   Correct the XQuery expression to return a single item sequence.  

请问有人知道怎么解决吗?

谢谢。

这可以作为输出吗?

TAG_NAME TAG_VALUE                                                             
-------- ----------------------------------------------------------------------
h2       <h2>title 1</h2>                                                      
h2       <h2>This is an <b>important</b> title</h2>                            
h3       <h3>This a subtitle b</h3>                                            
h3       <h3>This is also <span style="font-weight:500">important</span></h3>  

这对我来说更有意义 - 然后让您使用的任何 xml 工具根据需要解释标签值。 (他们可能要求标签值是 xmltype 数据类型——如果是这样,那么只需删除 select 子句中的 xmlserialize 包装器。)

如果可以接受,您只需稍微修改一下查询即可获得。

select tag_name, xmlserialize(document tag_value) as tag_value
from xmltable('body/*'  passing xmltype('<body><h2>title 1</h2>
  <h2>This is an <b>important</b> title</h2>Some text<h3>This a subtitle b</h3>
  <h3>This is also <span style="font-weight:500">important</span></h3></body>') 
columns 
  tag_name varchar2(1000) path 'name()',
  tag_value xmltype path '.')
where tag_name in ('h1','h2','h3','h4','h5')
;