BaseX-Talk September 2025

basex-talk@mailman.uni-konstanz.de

10 participants
7 discussions

XQuery version declarations and combinations
by Amanda Galtman 29 Sep '25

29 Sep '25

Hi, BaseX creators and users. I have several questions about XQuery versions: 1. The main documentation page [1] for BaseX 12.0 calls it an XQuery 4.0 processor. The XQuery 4.0 draft specification [2] says in section 5.1, "The XQuery 4.0 specification does not attempt to define the semantics of a query in which different modules use different version numbers. One approach is to process all modules as if they specified version "4.0". Another approach (which may be appropriate if modules are separately compiled) is to process each module using its own version number; but it is then implementation defined what happens if (say) a 3.1 module imports a 4.0 library module that declares a function with a signature that 3.1 does not recognize." The question is: What does BaseX do if a 3.0 main module imports a 1.0 library module? 2. That same section 5.1 says, "An XQuery 4.0 processor must accept a module in which the version number is given as "1.0", "3.0", or "3.1". It is then implementation defined whether the module is processed using the syntax and semantics of the XQuery 4.0 specification, or the rules of the relevant earlier version." What does BaseX do for pre-4.0 queries? 3. For the BaseX versions in the not-too-distant past that called themselves XQuery 3.1 processors, is the answer to question 2 analogous? (I don't see the same "processor must accept..." verbiage in the XQuery 3.1 specification [3], though.) 4. (Not BaseX-specific) If a main module declares version "1.0" and uses a post-1.0 feature like URI-qualified names, that's a bug in the module, right? Even if the main module imports a 1.0 module, and even if the processor doesn't complain about the post-1.0 feature usage? 5. (Not BaseX-specific) The 3.1 and 4.0 (draft) specifications explain the version declaration in terms of intent ("intent that the module be processed by an XQuery [...] processor"), which is a different criterion compared to stating the *minimum* XQuery version that would work for that module. If anyone on this list uses the "minimum" interpretation in practice, do you have any tips for efficiently determining the minimum required XQuery version for each module in a set of modules? The background behind my questions involves an XSpec test for an XQuery module, where the test gets compiled to a main module that imports the module you are testing. The main module uses features from 3.0, so I'm trying to determine the extent to which someone can test a 1.0 module using XSpec. Thanks, Amanda References: [1] https://docs.basex.org/main/Main_Page [2] https://qt4cg.org/specifications/xquery-40/xquery-40.html#id-version-declar… https://www.w3.org/TR/xquery-31/#id-version-declaration

2 2

db:drop error not being caught
by Lizzi, Vincent 29 Sep '25

29 Sep '25

Hi all, I have a query that is intended to delete outdated databases. This has been working but I recently found that if a database is locked the process stops with an error such as: [db:lock] Database 'name' cannot be updated, it is opened by another process. As a result, the process is stopped by any database being in a locked state. I would have thought that the try / catch around db:drop would catch the error and allow the process to skip over any locked databases. declare variable $age external := 'PT1M'; (: age 1 minute for testing :) let $cutoff := current-dateTime() - xs:dayTimeDuration($age) let $databases := db:list-details()[xs:dateTime(@modified-date) lt $cutoff] return ( admin:write-log('cleanup delete items older than ' || $cutoff), for $db in $databases return ( admin:write-log('cleanup deleting database ' || $db), try { db:drop($db) } catch * { admin:write-log('cleanup error deleting ' || $db || ': ' || $err:description, 'ERROR') } ) ) I tried replacing catch * with catch db:open to catch the specific error, but that hasn't helped. Why is the error not caught, and is there a better way to write this query to avoid this problem? Thanks, Vincent ______________________________________________ Vincent M. Lizzi Head of Information Standards | Taylor & Francis Group E-Mail: vincent.lizzi(a)taylorandfrancis.com<mailto:vincent.lizzi@taylorandfrancis.com> Web: www.tandfonline.com<http://www.tandfonline.com/> Time zone: US Eastern Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954 "Everything should be made as simple as possible, but not simpler." [cid:8d80b1b7-f927-4cb7-a971-709e53dbf8b7]<https://outlook.office.com/bookwithme/user/aa80d42cbb5b46dba06a5ad241d7665b…> Book time to meet with me<https://outlook.office.com/bookwithme/user/aa80d42cbb5b46dba06a5ad241d7665b…>

2 4

replacing elements with their children using update
by Graydon Saunders 27 Sep '25

27 Sep '25

Hello! So I can use copy $c := $test modify (for $each in $c/descendant::html:ins return replace node $each with $each/node()) return $c to unwrap all the html ins elements in some test HTML. If I try to do this using update (because I am under the perhaps mistaken impression that update can do the same things copy/modify/return can) $test update {replace node descendant::html:ins with 'CABBAGE'} works fine; the various ins elements are found and replaced. But if I want to replace that particular ins element with its children, there doesn't seem to be a way to specify the children; the context item is the value of $test, not whatever descendant ins element is being replaced. How could this be written using update? Can this be written using update? thanks! -- Graydon Saunders | graydonish(a)fastmail.com Þæs oferéode, ðisses swá mæg. -- Deor ("That passed, so may this.")

2 2

Add namespace bindings via copy/modify/return
by Hans-Juergen Rennau 25 Sep '25

25 Sep '25

Dear BaseX people, I cannot use copy/modify/return in order to add a namespacing: let $doc := <doc><a/></doc>return copy $doc_ := $doc modify insert node namespace xyz {'https://basex.org/ns'} into $doc_ return $doc_ =><doc> <a/></doc> Is this a bug? Kind regards,Hans-Jürgen

5 9

Multithreading issues after upgrade to BaseX 12
by Johannes Bauer 22 Sep '25

22 Sep '25

Hi, we experience some problems after the upgrade to version 12 with the fulltext search. We are using xquery:fork-join() to run the fulltext search on multiple databases at the same time (see attachment). This worked fine with version 11 but has strange effects after the upgrade to version 12. With BaseX 11 the log output is like this: 09:03:51.054 [0:0:0:0:0:0:0:1]:55079 admin REQUEST [POST] /dba/query?file=ftsearch.xq 09:03:51.203 SERVER admin TRACE local:search-db(ALL) 100.4 ms 09:03:51.204 SERVER admin TRACE local:search-db(ALL) 1721 09:03:51.243 SERVER admin TRACE local:matches() 38.84 ms 09:03:51.270 SERVER admin TRACE local:search-db(MD) 166.69 ms 09:03:51.270 SERVER admin TRACE local:search-db(MD) 1883 09:03:51.282 SERVER admin TRACE local:matches() 11.9 ms ... 09:03:52.284 SERVER admin TRACE local:search-db(XP) 307.84 ms 09:03:52.284 SERVER admin TRACE local:search-db(XP) 74128 09:03:52.525 SERVER admin TRACE local:matches() 241.64 ms 09:03:52.796 SERVER admin TRACE local:matches() 581.56 ms 09:03:52.796 SERVER admin TRACE local:search-distinct() search "test" 1710.79 ms 09:03:53.200 [0:0:0:0:0:0:0:1]:55079 admin 200 2160.7 ms After about 2 seconds the search is finished. With BaseX 12 two things might happen. ConcurrentModificationException This happens almost immediatelly. 500 Unexpected error: Improper use? Potential bug? Your feedback is welcome: Contact: basex-talk(a)mailman.uni-konstanz.de Version: BaseX 12.0 Java: Eclipse Adoptium, 21 OS: Windows 10, amd64 Stack Trace: java.util.ConcurrentModificationException at java.base/java.util.ArrayList$Itr.checkForComodification(ArrayList.java:1095) at java.base/java.util.ArrayList$Itr.next(ArrayList.java:1049) at org.basex.query.QueryResources.close(QueryResources.java:94) at org.basex.query.QueryContext.close(QueryContext.java:543) at org.basex.http.restxq.RestXqResponse.finish(RestXqResponse.java:152) at org.basex.http.web.WebResponse.create(WebResponse.java:63) at org.basex.http.restxq.RestXqServlet.run(RestXqServlet.java:70) at org.basex.http.BaseXServlet.service(BaseXServlet.java:68) at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:587) at org.eclipse.jetty.ee9.servlet.ServletHolder$NotAsync.service(ServletHolder.java:1397) at org.eclipse.jetty.ee9.servlet.ServletHolder.handle(ServletHolder.java:765) at org.eclipse.jetty.ee9.servlet.ServletHandler.doHandle(ServletHandler.java:528) at org.eclipse.jetty.ee9.nested.ScopedHandler.handle(ScopedHandler.java:127) at org.eclipse.jetty.ee9.security.SecurityHandler.handle(SecurityHandler.java:603) at org.eclipse.jetty.ee9.nested.HandlerWrapper.handle(HandlerWrapper.java:124) at org.eclipse.jetty.ee9.nested.ScopedHandler.nextHandle(ScopedHandler.java:197) at org.eclipse.jetty.ee9.nested.SessionHandler.doHandle(SessionHandler.java:612) at org.eclipse.jetty.ee9.nested.ScopedHandler.nextHandle(ScopedHandler.java:195) at org.eclipse.jetty.ee9.nested.ContextHandler.doHandle(ContextHandler.java:1045) at org.eclipse.jetty.ee9.nested.ScopedHandler.nextScope(ScopedHandler.java:164) at org.eclipse.jetty.ee9.servlet.ServletHandler.doScope(ServletHandler.java:483) at org.eclipse.jetty.ee9.nested.ScopedHandler.nextScope(ScopedHandler.java:162) at org.eclipse.jetty.ee9.nested.SessionHandler.doScope(SessionHandler.java:589) at org.eclipse.jetty.ee9.nested.ScopedHandler.nextScope(ScopedHandler.java:162) at org.eclipse.jetty.ee9.nested.ContextHandler.doScope(ContextHandler.java:966) at org.eclipse.jetty.ee9.nested.ScopedHandler.handle(ScopedHandler.java:125) at org.eclipse.jetty.ee9.nested.ContextHandler.handle(ContextHandler.java:1719) at org.eclipse.jetty.ee9.nested.HttpChannel$RequestDispatchable.dispatch(HttpChannel.java:1565) at org.eclipse.jetty.ee9.nested.HttpChannel.dispatch(HttpChannel.java:724) at org.eclipse.jetty.ee9.nested.HttpChannel.handle(HttpChannel.java:512) at org.eclipse.jetty.ee9.nested.ContextHandler$CoreContextHandler$CoreToNestedHandler.handle(ContextHandler.java:3029) at org.eclipse.jetty.server.handler.ContextHandler.handle(ContextHandler.java:1071) at org.eclipse.jetty.server.Server.handle(Server.java:182) at org.eclipse.jetty.server.internal.HttpChannelState$HandlerInvoker.run(HttpChannelState.java:678) at org.eclipse.jetty.server.internal.HttpConnection.onFillable(HttpConnection.java:416) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:322) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:99) at org.eclipse.jetty.io.SelectableChannelEndPoint$1.run(SelectableChannelEndPoint.java:53) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.runTask(AdaptiveExecutionStrategy.java:480) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.consumeTask(AdaptiveExecutionStrategy.java:443) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.tryProduce(AdaptiveExecutionStrategy.java:293) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.run(AdaptiveExecutionStrategy.java:201) at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:311) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:981) at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.doRunJob(QueuedThreadPool.java:1211) at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1166) at java.base/java.lang.Thread.run(Thread.java:1583) 189.44 ms Full text search never finishes 09:00:12.422 [0:0:0:0:0:0:0:1]:55041 admin REQUEST [POST] /dba/query?file=ftsearch.xq 09:00:12.633 SERVER admin TRACE local:search-db(ALL) 115.46 ms 09:00:12.635 SERVER admin TRACE local:search-db(ALL) 1721 09:00:12.672 SERVER admin TRACE local:matches() 37.09 ms 09:00:12.711 SERVER admin TRACE local:search-db(MD) 194.24 ms 09:00:12.711 SERVER admin TRACE local:search-db(MD) 1883 09:00:12.725 SERVER admin TRACE local:matches() 13.66 ms 09:00:12.851 SERVER admin TRACE local:search-db(LS) 334.48 ms 09:00:12.851 SERVER admin TRACE local:search-db(LS) 169524 09:00:12.923 SERVER admin TRACE local:search-db(CT) 406.58 ms 09:00:12.923 SERVER admin TRACE local:search-db(CT) 80086 ... 09:00:13.483 SERVER admin TRACE local:search-db(US) 47012 09:00:13.553 SERVER admin TRACE local:search-db(POC) 828.06 ms 09:00:13.554 SERVER admin TRACE local:search-db(POC) 10147 09:00:13.693 SERVER admin TRACE local:search-db(MR) 1020.89 ms 09:00:13.693 SERVER admin TRACE local:search-db(MR) 223155 The process "hangs" and never finishes and CPU is running on full load. The current database where it hangs is always a different one. Does this have anything to do with the Jetty update? It seems to be related to the multithreading. Best Regards Johannes

2 1

Who wants to take over the management of my RBaseX package?
by Ben Engbers 16 Sep '25

16 Sep '25

Since my retirement (five years ago), there has been no reason for me to program in R or to continue working on maintaining my RBaseX package. This package is still being downloaded, and in all the years it has been available on the internet, I have never received any questions about it. Maintaining it will therefore take very little time. When I do program, I use the C++ language (and I still hope to get my C++ client for BaseX bug-free). Is there anyone who would like to take over the management of RBaseX? Ben Engbers

1 0

load-xquery-module
by Rob Stapper 15 Sep '25

15 Sep '25

Hi Christian, I'm experimenting with dynamic modul loading using: 'load-xquery-module'. I have a few questions concerning this function: - Does this function cache the loaded modul like "import module" does? If I interpret the profiling data correcty, it does not. If so is it possible to also cache dynamicly loaded modules? - "location-hints" of this function accepts a set of locations. It seems that all these locations must contain a module with the given modul-uri. I would expect the one would be sufficient. What is the idea behind this locationset? Thanx in advance for your response. mvgr. Rob Stapper

2 1

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BaseX-Talk September 2025