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Problem in Java extension module
by Nico Verwer (Rakensi) 24 Apr '25

24 Apr '25

Greetings, BaseX creators and users! I am trying to make a custom XQuery function in Java. This works fine in most cases, but it seems to lose namespaces on attributes. The Java code in the function converts the BaseX representation of an element into a `org.w3c.dom.Element` DOM; transforms the DOM, creating a new DOM; sends the resulting DOM element back to BaseX. The problem is quite subtle and hard to explain in a few sentences. Therefore I have made a project demonstrating it, which can be seen on [Github](https://github.com/nverwer/possible-bug-in-BaseX). The project includes Java code and a simple XQuery that demonstrates the problem. I am at the point where I think the problem could be a bug in BaseX, which is why I thought it would be a good idea to post this to the basex-talk mailing list. If someone with more knowledge of the inner workings of BaseX could help me, I would much appreciate. Best regards, Nico Verwer

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Way to record node IDs that does not depend on database name?
by Eliot Kimber 22 Apr '25

22 Apr '25

In my long-running data load process that appears to fail, I’ve found the issue but I don’t see an obvious way to correct it. My process creates a temporary content database that contains the latest content version of content previously loaded. This temp database is then the source for a process that creates a set of where-used index records in another database that point to the nodes in the temp content database by node ID. The node-recording elements look like this: <noderef node-id="43617" database="pce-test-data" tagname="mapref" baseuri="/pce-test-data/encryption-support.ditamap" href="cloud-encryption.ditamap" /> Note the “database” attribute: it’s the name of the database the node ID is from. After the process as completed constructing all the where-used records and is ready to swap these new databases into production, I have an XSLT transform that updates the values of the @database attributes to replace the temporary database name with the production name (i.e., remove leading “_temp_” from the database name. I then swap the temp databases in place of the old databases, putting the new data into production. This works fine at small scales, but when I attempt it with my 200K-link database, the XSLT transform either simply never completes or fails in the backgroujnd or would take so long to complete that it would be impractical. In any case, this approach does not work for my full-scale case ☹ So my question is: How can avoid this need to update my node reference elements to reflect the new database name? One solution that comes to mind is simply not recording the database name on the <noderef> element but somewhere else, say in the root element of the document that contains the <nodere>, but that requires that all the <noderef> elements in that context target the same database, which will be true in this case but might not be true in the future (I had designed <noderef> to enable mixing references to nodes in different databases). I could also have the code that’s creating these where-used records manage the prod-to-temp database name dynamically (and that may be my best solution the more I think about it) but starts to look like magic and I try to avoid magic code. So a solution that is less fragile would be ideal. Changing the value requires an update of some sort, whether it’s via XSLT or XQuery update, it’s going to be problematic at this scale. Is there any solution I’ve overlooked? Thanks, Eliot _____________________________________________ Eliot Kimber Sr. Staff Content Engineer O: 512 554 9368 servicenow servicenow.com<https://www.servicenow.com> LinkedIn<https://www.linkedin.com/company/servicenow> | X<https://twitter.com/servicenow> | YouTube<https://www.youtube.com/user/servicenowinc> | Instagram<https://www.instagram.com/servicenow>

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Runtime error from DBA log viewer
by Eliot Kimber 19 Apr '25

19 Apr '25

Trying to view today’s log, I get this runtime failure: Stopped at /data1/basex/webapp/dba/logs/logs.xqm, 220/25: [FORG0001] Cannot convert to xs:decimal: 3.4345182E+8. Stack Trace: - /data1/basex/webapp/dba/logs/logs.xqm, 157/10 266.98 ms I can provide the log file separately. This is with BaseX 11.6 Cheers, Eliot _____________________________________________ Eliot Kimber Sr. Staff Content Engineer O: 512 554 9368 servicenow servicenow.com<https://www.servicenow.com> LinkedIn<https://www.linkedin.com/company/servicenow> | X<https://twitter.com/servicenow> | YouTube<https://www.youtube.com/user/servicenowinc> | Instagram<https://www.instagram.com/servicenow>

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Parallelizing writes to a database
by Eliot Kimber 18 Apr '25

18 Apr '25

In my Mirabel system, I create a link database that records all the links made in a set of documents. This becomes a “where used” index over the content. We have on the order if 200K links for one content set, so at 0.1 second per link it takes about 7 hours to build this index. I’m currently doing this in one process that builds the whole index and then stores it in a database. This is failing in hard-to-diagnose ways, for example, because a database has a write lock on it when I go to rename it from it’s temp name to it’s production name (to replace the current production version). The data is such that I could parallelize the processing but I’m not sure how I would do that in BaseX so that I can safely write to a single database from multiple threads. The fork-join() docs clearly say “non-updating” functions, so that doesn’t seem to be an option. I have multiple BaseX HTTP servers running so I could farm processing across them, but I think I would then run into write lock issues. I could create separate databases for each thread of operation and then combine those at the end—that seems like it might be the best option. Have I missed anything? Thanks, Eliot _____________________________________________ Eliot Kimber Sr. Staff Content Engineer O: 512 554 9368 servicenow servicenow.com<https://www.servicenow.com> LinkedIn<https://www.linkedin.com/company/servicenow> | X<https://twitter.com/servicenow> | YouTube<https://www.youtube.com/user/servicenowinc> | Instagram<https://www.instagram.com/servicenow>

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Bug report - argument = context item, param value several items
by Hans-Juergen Rennau 10 Apr '25

10 Apr '25

Dear BaseX people, I have encountered a bug (?). Please consider this code: = = = = = = = = = begin = = = declare namespace f="http://weatherreport.org/heavyweather"; declare function f:relatedNames($node, $relationship) as xs:string* { let $fnName := function($node) { let $_DEBUG := trace(count($node), '#node: ') return name($node)} let $items := switch($relationship) case 'child' return $node/* default return error() return $items/$fnName(.) => distinct-values() => sort() => string-join(', ')}; let $doc := <doc><a/><b/><c/></doc>return f:relatedNames($doc, 'child') = = = = = = = = = end = = = = = = = = = = = = output = = =#node: 3Stopped at C:/projects/foxpath-examples/pre-balisage/problem-basex2.xq, 15/25:[XPTY0004] Item expected, sequence found: (<a/>, <b/>, <c/>).= = = = = = = = = = = = = = = = The call $fnName(.) receives a single item, but three items arrive at the function item! With kind regards,Hans-Jürgen PS: The funny switch() seems to play a part in the game, when I removed it, the issue vanished.PPS: BaseX 11.8 [Standalone]

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Execution of let clauses versus optimization
by Hans-Juergen Rennau 06 Apr '25

06 Apr '25

Dear BaseX people, I observe a behaviour which appears to me not desirable, although it is, strictly speaking, correct. Please consider this code: let $fnCopy := function($term) {trace('yes', 'within fnCopy: ')} let $_DEBUG := trace('before call fnCopy') let $result := $fnCopy('yogi') (: let $_DEBUG := if ($result eq 'NEVER') then error() else () :) let $_DEBUG := trace('after call fnCopy') return () As long as the commented out clause is not activated, the function is *not* executed. It is strictly speaking correct behaviour: the processor may optimize and skip the call of $fnCopy, as it does not contribute to the value of the containing FLWOR expression. However, when using functions with side-effects (as file:write()), it is of course necessary to be sure that the call is executed. Contrary to other processors, according to my experience BaseX has never skipped let clauses for reasons of optimization, and in many years of usage I have again and again highly appreciated this behaviour. The skipping behaviour is new to me. Is it so that BaseX has changed its policy concerning let clauses not contributing to the FLWOR result? It would be very important to know, because the execution of functions with side effects is everyday practice. Kind regards,Hans-Jürgen

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11.8: Store always clearing on restart
by Zimmel, Daniel 26 Mar '25

26 Mar '25

Hi, is this a bug? The store is always clearing on restart. In contrast, the documentation says: "The store will still be available if BaseX is restarted until it is cleared." https://docs.basex.org/main/Store_Functions It works as documented in 11.6, but not in 11.7 and 11.8. Steps to reproduce via GUI: 11.6: Start GUI XQuery: store:put('TEST','TEST') Close GUI Start GUI XQuery: store:get('TEST') Result: 'TEST' 11.7/8: Start GUI XQuery: store:put('TEST','TEST') Close GUI Start GUI XQuery: store:get('TEST') Result is empty The changelog for 11.7 says (not related?): [MOD] Store functions: only read if contents have changed (https://basex.org/2025/01/31/basex-11.7/) Cheers, Daniel

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Re: document-uri() and base-uri() functions in BaseX 11.8
by ykhabins＠bellsouth.net 25 Mar '25

25 Mar '25

Hi Gunther, I tested the latest build, BaseX 11.9 beta c55e0e8 Everything is back to normal. The document-uri() and base-uri() functions working as expected. Thanks a lot for such quick turn-around with the fix. Regards, Yitzhak Khabinsky

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Re: document-uri() and base-uri() functions in BaseX 11.8
by ykhabins＠bellsouth.net 25 Mar '25

25 Mar '25

Hi Gunter, I tested the latest build, BaseX 11.9 beta c55e0e8 Everything is back to normal. The document-uri() and base-uri() functions working as expected. Thanks a lot for such quick turn-around with the fix. Regards, Yitzhak Khabinsky

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document-uri() and base-uri() functions in BaseX 11.8
by ykhabins＠bellsouth.net 25 Mar '25

25 Mar '25

Hello, Congrats on the BaseX 11.8 release. Was there a change in BaseX 11.8 to the document-uri() and base-uri() functions behavior? It seems that they are striping out a file name at the end of the fully qualified file path on the file system! Please find below a repro of it. BaseX 11.7 ========== declare variable $base_dir as xs:string := 'e:\Temp\Identity Transformation88\'; for $x at $i in collection($base_dir) let $file := tokenize(document-uri($x), '/')[last()] return (document-uri($x), $file) Emits the following as expected: file:///E:/Temp/Identity%20Transformation88/Input.xml Input.xml file:///E:/Temp/Identity%20Transformation88/Output.xml Output.xml BaseX 11.8 ========== The same XQuery emits the following: file:///E:/Temp/Identity%20Transformation88/ file:///E:/Temp/Identity%20Transformation88/ Regards, Yitzhak Khabinsky

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