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docs/en/sql-reference/functions/string-functions.md
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@ -655,15 +655,16 @@ Result:
The function extracts text from HTML or XHTML according to the following rules. The function extracts text from HTML or XHTML according to the following rules.
1. Comments starting with `<!--` and ending with `-->` are removed. 1. Comments starting with `<!--` and ending with `-->` are removed.
1. The content of a `CDATA` section is left as is, without furthure processing. 1. The content of a `CDATA` section between `<![CDATA[` and `]]>` is left as is, without furthure processing. Note that it is appended to the previous text without any space.
1. Text wrapped with `<script>` or `<style>` tags is removed entirely. 1. A text wrapped with `<script>` or `<style>` tags is removed entirely. If `script` or `style` are the names of XML namespaces (like `<script:a>`) then they are treated like usual tags.
1. Any tag is replaced with a space. 1. Any tag is replaced with a space. Note that elements like `<>`, `<!>`, `<!-->` are also replaced. Tag without closing bracket `>` is removed to the end of an input text.
1. Consecutive whitespaces (space, new line, line feed, tab characters) are converted to a single space. 1. Any sequence of whitespaces (space, new line, carriage return, tab, vertical tab or form feed) is converted to a single space.
1. Leading and trailing spaces are removed. 1. Leading and trailing spaces are removed from the returned text.
!!! info "Note" !!! info "Note"
HTML and XML entities are not decoded. HTML and XML entities are not decoded by the extractTextFromHTML function.
It is not guaranteed that the function fully supports all HTML, XML or XHTML standards. But it tries to do the best.
It is not guaranteed that extractTextFromHTML function fully supports all HTML, XML or XHTML standards. But it tries to do the best.
**Syntax** **Syntax**
@ -689,13 +690,13 @@ The second example shows CDATA and script tag processing.
Query: Query:
``` sql ``` sql
SELECT extractTextFromHTML(' <p> Text <i>inside</i><b>tags</b>. <!-- comments --> </p> '); SELECT extractTextFromHTML(' <p> Text <i>with</i><b>tags</b>. <!-- comments --> </p> ');
SELECT extractTextFromHTML('<![CDATA[The content within <b>CDATA</b>]]> <script>alert("Script");</script>'); SELECT extractTextFromHTML('<![CDATA[The content within <b>CDATA</b>]]> <script>alert("Script");</script>');
``` ```
Result: Result:
``` text ``` text
Text inside tags . Text with tags .
The content within <b>CDATA</b> The content within <b>CDATA</b>
``` ```