db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Kristian Waagan <Kristian.Waa...@Sun.COM>
Subject Re: XML in Derby - WAS : [jira] Updated: (DERBY-688) Enhancements to XML functionality to move toward XPath/XQuery support...
Date Tue, 29 Aug 2006 22:39:32 GMT
Daniel John Debrunner wrote:
> David Van Couvering wrote:
>> Wow, great work Army, and thanks for the careful review and effort by
>> Brian and Yip!  It's great to have this in.  If I could only grok
>> exactly what the feature is and how I might use it :)  I am telling
>> people "we have XML features" and I know it's something to do with
>> XQuery and XPath, but I couldn't say what.
> I was messing with the XML support last night for buddy testing and it's
> very cool. Three new Derby features combined together to make the
> application development easier:
> 1) XML support
> 2) CALL procedure in trigger
> 3) Lengthless overrides for PreparedStatement.setCharacterStream
> OK - I didn't test 3) cos I would have to set up Xalan for Mustang and I
> didn't want to spend time on how to figure that out, but it would have
> been useful.

Hi Dan,

This sounds really cool :)
Any change you can share your trigger procedure?
Then maybe someone else can take on the work to test the new lengthless 
overrides added by JDBC 4.0. I don't think they have received much 
testing yet. They are now in the 10.2 branch, but I believe they are not 
(fully) included in the latest beta ( I'll add an entry to the 
buddy testing page when the time is right.


> I setup a table with a column that contained a URL as a VARCHAR and an
> XML column, a procedure in an INSERT trigger then fetched the data from
> the URL and updated the XML column using XMLPARSE, streaming directly
> from the remote site using setCharacterStream.
> I used this to download DERBY Jira issues, each row holds an XML
> document that corresponds to a single Jira issue. E.g. from
> http://issues.apache.org/jira/browse/DERBY-434?decorator=none&view=rss
> Then I can execute queries against the issues locally, using XPath (and
> SQL).
> -- Sequence of all comments made by Sunitha against bugs reported by me
> --  wd_id is the DERBY-XXX identifier
> --  wd_accesstime is the time the data was downloaded from the web.
> --  wd_content is the XML column
> select wd_id, wd_accesstime,
> XMLQUERY('//item/comments/comment[@author="skambha"]' PASSING BY REF
> wd_content EMPTY ON EMPTY)
> AS VARCHAR(30000))
> from wdd.web_docs where
> XMLEXISTS('//reporter[text() = "Daniel John Debrunner"]' PASSING BY REF
> wd_content);
> -- Jira status of all bugs entered by me
> select wd_id,
> XMLQUERY('//item/status/text()' PASSING BY REF wd_content EMPTY ON EMPTY)
> AS VARCHAR(20)),
> wd_accesstime
> from wdd.web_docs where
> XMLEXISTS('//reporter[text() = "Daniel John Debrunner"]' PASSING BY REF
> wd_content)
> order by 2,1;
> I'll think I wil expand this to use it in my talk at ApacheCon US.
> Dan.

View raw message