- BaseX-Talk - mailman.uni-konstanz.de

Database housekeeping for newbies
by Sam Eklund 05 Nov '12

05 Nov '12

Hey all! I am considering BaseX to hold event information for a broadcast graphics play out system. This system gets a lot of event data from the planning system. Each segment can have up to 12 events, and a day in a typical commercial tv-channel has about 120-160 segments. The commercial breaks not included. Every time a full day of programming is made for a channel, an xml file is produced containing a lot of (badly formatted) EVENT nodes, below a typical "coming next" event: <EVENT IDdeko="109213416" DATE="2012-09-21" CHANNEL_ID="123" VIDEOFORMAT="2"> <SCENARIO ID="29"> <METADATA pos="0" value="00:20"/> <METADATA pos="1" value="The Godfather pt III"/> <METADATA pos="2" value="American drama from 1990 with Al Pacino and Andy Garcia"/> </SCENARIO> </EVENT> I have manually created a database from one of these export xml files and manged to call a BaseXClient dll that I compiled from your examples to retrieve data from the database. All is well with that. Now to my question, since I'm not really familiar with databases in general... Is it possible to set up a "watch folder" for the incoming xml files that will add them to a specified database or would I have to create an application for this? The second question is about housekeeping, since we are handling about 20 channels with this database, the number of events in the database will increase quite fast. Is it possible to specify an xpath search that would match all events with a date more than X days back in time and delete them from the database, i.e delete data from the database without calling the exact file the data was imported with? Best regards SamTheSwede Stockholm

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BaseX Scala Client 0.5 released, this time with documentation
by Manuel Bernhardt 04 Nov '12

04 Nov '12

Hi all, I finally found / forcefully took the time and documented the Scala Client library. The new release mostly brings documentation and uses BaseX 7.3. We have been using it for 5 months now and it works nicely. One interesting feature if you're dealing with queries that return large quantities of documents (and use Scala...) is the StreamingClientSession which doesn't cache incoming results but directly passes them on to be consumed by the client code. Check it out here: https://github.com/delving/basex-scala-client Cheers, Manuel

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pre values and add-only dbs
by Fabrice Etanchaud 03 Nov '12

03 Nov '12

Dear all at BaseX, Can pre values change in add-documents-only databases ? Can pre values change in add/delete-documents-only databases ? Here is the big picture : I have a Document DB, references by a Index DB which stores (key,pre) couples, Where pre are pre values in the Document DB. Document DB documents are only added (or sometimes deleted). Do I have to use id values or can I use pre values ? Best regards Fabrice Etanchaud Questel-Orbit

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Create DB fails with 'Input is too large for a single database'
by Fabrice Etanchaud 01 Nov '12

01 Nov '12

Dear all at BaseX, Once again, thank you for your job ! A Database creation fails after some time, With the message 'Input is too large for a single database'. It seems to be related with the LIMITRANGE error message. Could you please give us a few explanations, And a way to import the data (about 81 Go) anyway ? Best regards, Fabrice Etanchaud Questel-Orbit

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Setting User-Agent for http:send-request?
by Erol Akarsu 01 Nov '12

01 Nov '12

Hi, I am trying to set User-Agent header attribute for an HTTP request with following code snippet. let $content := http:send-request(<http:request method='get' status-only='false' User-Agent='Mozilla/5.0'/>, $url) let $body := $content[2] return $body But It is sending "Java/1.7.0_02" as User-Agent header attribute. This has been taken from wireshark: GET / HTTP/1.1 User-Agent: Java/1.7.0_02 Host: istanbul.olx.com.tr Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2 Connection: keep-alive Do we have any way to set the user-agent attribute? Thanks Erol Akarsu

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Calling static Java function from XQuery
by The Trainspotter 01 Nov '12

01 Nov '12

Hi, I followed the docs and examples on calling Java functions from XQuery, but when I try and add a package to the repository that calls one of my own functions BaseX complains that it can't find the function. I am running BaseX locally and the class I want to call is in my project's classpath. Any ideas as to what I'm doing wrong? Cheers Gary

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Re: [basex-talk] Database housekeeping for newbies
by pw＠themail.co.uk 31 Oct '12

31 Oct '12

Think about using the Mule ESB [ http://www.mulesoft.com/mule-esb-open-source-esb ] or similar and then feed in to webservices from the service bus Peter ---- Original Message ---- From: gaerber(a)axxepta.de To: basex-talk(a)mailman.uni-konstanz.de Subject: Re: [basex-talk] Database housekeeping for newbies Date: Wed, 31 Oct 2012 15:00:09 +0100 >Hi, > >I don't know of any hot-folder mechanism in basex but you might be >interested in the webdav api: http://docs.basex.org/wiki/WebDAV > >Concerning the housekeeping, I'd create new databases containing a >defined time period (e.g. one week or so). You can query several >databases at once, so you always have the option to: > >- query over single or multiple time periods >- drop a complete time period > >Changing a lot of nodes (or deleting) inside a single database is >sometimes slow. But that might be due the structure of my data. > >Regards, > >Max > > >2012/10/31 Sam Eklund <sam.eklund(a)gluebox.se>: >> Hey all! >> >> >> >> I am considering BaseX to hold event information for a broadcast >graphics >> play out system. This system gets a lot of event data from the >planning >> system. Each segment can have up to 12 events, and a day in a >typical >> commercial tv-channel has about 120-160 segments. The commercial >breaks not >> included. >> >> >> >> Every time a full day of programming is made for a channel, an xml >file is >> produced containing a lot of (badly formatted) EVENT nodes, below a >typical >> coming next event: >> >> >> >> <EVENT IDdeko="109213416" DATE="2012-09-21" CHANNEL_ID="123" >> VIDEOFORMAT="2"> >> >> <SCENARIO ID="29"> >> >> <METADATA pos="0" value="00:20"/> >> >> <METADATA pos="1" value="The Godfather pt III"/> >> >> <METADATA pos="2" value="American drama from 1990 with Al >Pacino and >> Andy Garcia"/> >> >> </SCENARIO> >> >> </EVENT> >> >> >> >> I have manually created a database from one of these export xml >files and >> manged to call a BaseXClient dll that I compiled from your examples >to >> retrieve data from the database. All is well with that. Now to my >question, >> since Im not really familiar with databases in general >> >> >> >> Is it possible to set up a watch folder for the incoming xml >files that >> will add them to a specified database or would I have to create an >> application for this? >> >> >> >> The second question is about housekeeping, since we are handling >about 20 >> channels with this database, the number of events in the database >will >> increase quite fast. Is it possible to specify an xpath search that >would >> match all events with a date more than X days back in time and >delete them >> from the database, i.e delete data from the database without >calling the >> exact file the data was imported with? >> >> >> >> >> >> Best regards >> >> >> >> SamTheSwede >> >> Stockholm >> >> >> >> >> >> >> >> >> _______________________________________________ >> BaseX-Talk mailing list >> BaseX-Talk(a)mailman.uni-konstanz.de >> https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk >> > > > >-- > >Maximilian Gärber > >axxepta solutions GmbH >Postfach 51 02 38 >13362 Berlin > >Tel +49 (0)30 499 147 66 >Fax +49 (0)30 499 147 67 >Mail gaerber(a)axxepta.de >_______________________________________________ >BaseX-Talk mailing list >BaseX-Talk(a)mailman.uni-konstanz.de >https://mailman.uni-konstanz.de/mailman/listinfo/basex-talk

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id function in BaseX
by Massimo Franceschet 31 Oct '12

31 Oct '12

Hi. I'm trying to use the XPath id function with BaseX (GUI interface) with no success. For instance, I'm querying the bibliographic XML document found at http://users.dimi.uniud.it/~massimo.franceschet/caffe-xml/xpath/xpath-synta… with the id queries written below in this page, for instance, id("M4M05"). The query is parsed correctly by BaseX but the result is always empty. Cheers, Massimo Franceschet

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Navigating a DOM
by Rainer Klute 29 Oct '12

29 Oct '12

Hi, I did some first steps with BaseX, but unfortunately I was not very successful. I have a really large XML file which does not fit into memory, and I would like to navigate it as a DOM. My hope was that I could store it as a BaseX database, retrieve the root element as a org.w3c.dom.Node, and then start navigating down and up the DOM as needed without having to have the whole stuff in memory. I tried something like this: QueryProcessor processor = new QueryProcessor("doc('catalog')/*", context); Iter iter = processor.iter(); Item item = iter.next(); Object node = item.toJava(); According to the debugger the item variable indeed denoted my root element. However, when calling item.toJava() not only that very node was returned. Instead BaseX obviously tried to retrieve the whole DOM – which was just the very thing I wanted to avoid. Am I doing something wrong here? Or is this an unforeseen use case? By the way, I also had trouble getting any result at all. Only with "doc('catalog')/*" I got an item that was not null. When I tried to retrieve all elements named "article" using "doc('catalog')//article" the item was null. I also tried the item.iter() in order to find a node's children. However, it turned out that item().iter().next() == item. And I had quite a tough time fiddling around with the documentation and with the JavaDoc. While the documentation puts a lot of effort into XQuery, it remains unclear to some extend how to do some basic stuff with BaseX programmatically. This is a hurdle for the BaseX beginner. Some more Java examples and explanations would be nice showing how to connect to the database, submit a query and process the result. Currently the examples show only how to dump a query result to System.out. It would be interesting to learn about processing it further – see my troubles with Iter. -- Best regards Rainer Klute

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Bug in document order
by Hans-Juergen Rennau 29 Oct '12

29 Oct '12

Hello, I noticed a little bug concerning document order. Consider this input: === in.xml ==================================== <section> <title>Some title</title> </section> ============================================ and the following query, which (a) extends the contents of <section> by a <para> element (=> $result) (b) and then makes a simple copy of the intermediate result (=> $copy): === problem.xq =============================== let $in := /* let $result := element {node-name($in)} { $in/*, <para>APPENDED ELEMENT</para> } let $copy := element {node-name($result)} {$result/*} return <wrap>{ <result>{$result}</result>, <copy>{$copy}</copy> }</wrap> ============================================= Launching the query basex -i in.xml problem.xq one gets a result in which the contents of $copy are in the wrong order (<para> comes now before <title>, though it should come last). Kind regards, Hans-Juergen The query result: ============================================= <wrap> <result> <section> <title>Some title</title> <para>APPENDED ELEMENT</para> </section> </result> <copy> <section> <para>APPENDED ELEMENT</para> <title>Some title</title> </section> </copy> </wrap> =============================================

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