Add support for XPath functions

[weijiii]

Description

• Fixes Support for XPath functions #3888
• Supersedes Add support for XPath scalar functions - xpath,xpath_string,xpath_boolean,xpath_double #9219

Additional context and related issues

• The case with XPathConstants.NODE is not utilized in both Hive and Spark. xpath_node may not be needed here. For now the behavior is following that of the case with NODESET, returning the content provided by Node#getNodeValue

Release notes

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# General
* Add support for XPath functions. ({issue}`3888`)

[findepi]

cc @nineinchnick

[weijiii]

@nineinchnick Can you take a look when you get a chance? Thanks!

[nineinchnick]

I'd love to have these functions available, but @martint has to review it, as the function names and signatures need to be approved by him first.

[weijiii]

I'd love to have these functions available, but @martint has to review it, as the function names and signatures need to be approved by him first.

Oh sure no worries! Thanks

[martint]

We should look into whether there's any precedent for this in the SQL specification or other databases before we settle on specific syntax and semantics.

[github-actions]

This pull request has gone a while without any activity. Tagging the Trino developer relations team: @bitsondatadev @colebow @mosabua

[mosabua]

Added stale-ignore label to keep this PR open.

@weijiii could you provide some information about precedent in the SQL specification or other databases

This will help us decide a path forward and help with reviews by @martint and others.

[weijiii]

Added stale-ignore label to keep this PR open.

@weijiii could you provide some information about precedent in the SQL specification or other databases

This will help us decide a path forward and help with reviews by @martint and others.

I did not get to work on this PR for a while. I will look into it

[chgl]

Very interested in this as well! To add some data points:

1. in PostgreSQL there's xpath and xpath_exists (https://www.postgresql.org/docs/16/functions-xml.html#FUNCTIONS-XML-PROCESSING)
2. in Oracle SQL there's the now deprecated EXTRACTVALUE (https://docs.oracle.com/en/database/oracle/oracle-database/19/sqlrf/EXTRACTVALUE.html) - the successor functions technically uses XQuery.
3. In MySQL there's an ExtractValue as well (https://dev.mysql.com/doc/refman/8.4/en/xml-functions.html#function_extractvalue)

The ANSI SQL standard has a part on XML: https://webstore.ansi.org/standards/iso/isoiec9075142023 which I don't have access to, but a preview is available at: https://webstore.ansi.org/preview-pages/INCITS/preview_INCITS+ISO+IEC+9075-14-2008.pdf