Re: WIP - xmlvalidate implementation from TODO list

út 31. 3. 2026 v 11:29 odesílatel Jim Jones <jim(dot)jones(at)uni-muenster(dot)de>
napsal:

>
>
> On 30/03/2026 22:28, Pavel Stehule wrote:
> > I checked db2 doc, and if I understand their doc, the XML schema is
> > identified by "relational identifier" SQLschema.name
> >
> > So taking XML schema as catalog object is the correct analogy and using
> > acl looks to me correct.
>
> +1
>
> > But what is different (patch and db2), one relational identifier can
> > identify a group of XML schemas. So there is relation 1:N not 1:1. You
> > can see the REGISTER XMLSCHEMA command.
>
> I wonder what are the applications for this 1:N relationship between xml
> schemas and their identifiers. Sounds cool though.
>

I found
https://www.developpez.net/forums/d540201/bases-donnees/db2/validation-xml-db2-v9-5-a/

> > The schema registration is different on MSSQL where it is more similar
> > to some local cache, and schema is identified only by uri. In this case
> > using ACL can be messy, and I can imagine having some dedicated role
> > that can register a new xml schema. But MSSQL doesn't support SQL/XML
> > XMLVALIDATE function.
> >
> > Both concepts are workable, and I have no strong preference for one or
> > second (maybe DB2 concept is better for Postgres, probably DB2 concept
> > is closer to SQL/XML). But if we use relational identifiers, then it
> > should be consistent with other usage of relational identifiers - there
> > ACL should be used.
>
>
> A few other things I noticed in v6
>
> == event triggers (event_trigger.c) ==
>
> OBJECT_XMLSCHEMA is in the elog(ERROR) path of stringify_grant_objtype()
> and stringify_adefprivs_objtype(). Since the grammar does support
> GRANT/REVOKE ... ON XMLSCHEMA, any event trigger on ddl_command_end that
> fires during a GRANT on an XML schema will raise a elog(ERROR,
> "unsupported object type").
>
> An additional test here would be nice as well.
>
> == corrupt dump ==
>
> pg_dump is ignoring GRANT statements. Since the feature supports
> GRANT/REVOKE on XMLSCHEMAS, omitting ACL dump means privileges are
> silently lost during dump/restore.
>
> == inconsistent DDL statements ==
>
> The docs suggest that ALTER XMLSCHEMA ... IF EXISTS is supported, which
> isn't the case. It should be either implemented or just removed from the
> docs.
>
> == different error message for build without libxml ==
>
> In xml.c the error messag used is "unsupported XML feature", but you're
> using "xmlschema support requires libxml" in pg_xmlschema.c. I think we
> should be consistent here.
>
> Thanks!
>
> Best, Jim
>
>
>
>