XQuery is an extension of XPath. Here's an example in XPath. These things are
easiest to understand if we know the structure of your docs. Suppose I insert:
xdmp:document-insert("test.xml",
<note><date-taken>2015-01-01</date-taken></note>)
I could find the count of docs more than two years old like this:
count(/note[fn:days-from-duration(fn:current-date() - date-taken) > (365 * 2)])
Sam Mefford
Senior Engineer
MarkLogic Corporation
sam.meff...@marklogic.com
Cell: +1 801 706 9731
www.marklogic.com<http://www.marklogic.com>
This e-mail and any accompanying attachments are confidential. The information
is intended solely for the use of the individual to whom it is addressed. Any
review, disclosure, copying, distribution, or use of this e-mail communication
by others is strictly prohibited. If you are not the intended recipient, please
notify us immediately by returning this message to the sender and delete all
copies. Thank you for your cooperation.
________________________________
From: general-boun...@developer.marklogic.com
[general-boun...@developer.marklogic.com] on behalf of Ladner, Eric
(Eric.Ladner) [eric.lad...@chevron.com]
Sent: Thursday, August 24, 2017 2:24 PM
To: MarkLogic Developer Discussion
Subject: [MarkLogic Dev General] Noob query question..
I’m still rather new to MarkLogic and apparently have a lot to learn. When
doing research on a proof of concept, I ran across a situation that would be
trivial to solve in SQL, but I’m having problems wrapping my head around how to
do that in XQuery. Or, is XQuery even the right place for this?
Basically, the number of notes per subject for any note that’s less than two
years old. If I was to do this in SQL, it’d look something like:
select subject, count(*) from notes where date_taken > sysdate-(365*2) group
by subject;
There’s some additional WHERE clause stuff for filtering, but on average, the
number of results shouldn’t be large.
Any guidance on building up more complex queries like this? The documentation
is semi-helpful, but the examples it gives for usage are usually very
simplistic.
Eric Ladner
Systems Analyst
eric.lad...@chevron.com<mailto:eric.lad...@chevron.com>
_______________________________________________
General mailing list
General@developer.marklogic.com
Manage your subscription at:
http://developer.marklogic.com/mailman/listinfo/general
