BaseX-Talk May 2020

basex-talk@mailman.uni-konstanz.de

24 participants
31 discussions

GUI "create db" file patterns are not sticky
by Graydon Saunders 12 May '20

12 May '20

This is a very small feature request. Everything else about the Create Database GUI is sticky -- when changed it stays changed -- EXCEPT the file patterns. Would it be possible to make the file patterns sticky as well? I often need to create a new database repeatedly since I'm using XQuery to test output from XSLT processes during development. Remembering to add all the file patterns is not excessively burdensome but I would like to not have to do it. Thanks! Graydon

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Query optimizer bug with nested for? - java.lang.NullPointerException at Path.index(Path.java:673)
by Sebastian Guerrero 11 May '20

11 May '20

Hi everybody! Maybe it's a newbie issue, but I would like your comments. I'm writing a RESTXQ method to search among a couple of databases. ( >100 databases ) Some databases are split into a couple of parts due to the number of nodes. For example US: it's separated into US00, US01 and US02. So, my problem is: if I replace "*for $usPart in ('US00')*" by "*for $usPart in ('US00','US01',''US02)*" in *QUERY [A]*, I get this error: *Improper use? Potential bug? Your feedback is welcome:* *Contact: basex-talk(a)mailman.uni-konstanz.de <basex-talk(a)mailman.uni-konstanz.de>* *Version: BaseX 9.3.2* *Java: Oracle Corporation, 1.8.0_251* *OS: Windows 10, amd64* *Stack Trace: * *java.lang.NullPointerException* * at org.basex.query.expr.path.Path.index(Path.java:673)* * at org.basex.query.expr.path.Path.optimize(Path.java:157)* * at org.basex.query.expr.gflwor.For.toPredicate(For.java:220)* * at org.basex.query.expr.gflwor.GFLWOR.optimizeWhere(GFLWOR.java:532)* * at org.basex.query.expr.gflwor.GFLWOR.optimize(GFLWOR.java:109)* * at org.basex.query.expr.gflwor.GFLWOR.compile(GFLWOR.java:100)* * at org.basex.query.expr.Extension.compile(Extension.java:45)* * at org.basex.query.expr.SwitchGroup.compile(SwitchGroup.java:40)* * at org.basex.query.expr.Switch.compile(Switch.java:60)* * at org.basex.query.expr.gflwor.GFLWOR.compile(GFLWOR.java:96)* * at org.basex.query.expr.gflwor.ForLet.compile(ForLet.java:43)* * at org.basex.query.expr.gflwor.GFLWOR.compile(GFLWOR.java:90)* * at org.basex.query.scope.MainModule.comp(MainModule.java:81)* * at org.basex.query.QueryCompiler.compile(QueryCompiler.java:114)* * at org.basex.query.QueryCompiler.compile(QueryCompiler.java:105)* * at org.basex.query.QueryContext.compile(QueryContext.java:312)* * at org.basex.query.QueryProcessor.compile(QueryProcessor.java:79)* Using "*for $usPart in ('US00')*" it works without any problem. With one element there is no problem, with two or more it fails. Any ideas about what I'm doing wrong? Here is the *QUERY [A]* ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- declare namespace gb="http://www.ipo.gov.uk/schemas/tm"; let $text:="christian" let $registries:=('GB','US') let $results := for $registry in $registries return switch ($registry) case "US" return (# db:enforceindex #) { for $usPart in ('US00') for $tmUS in db:open($usPart)/trademark-applications-daily/application-information/file-segments/action-keys/case-file where $tmUS/case-file-header/mark-identification/text() contains text {$text} using stemming return <trademark><ipo>US</ipo><text>{$tmUS/case-file-header/mark-identification/text()}</text></trademark> } case "GB" return (# db:enforceindex #) { for $tmGB in db:open('GB')/gb:MarkLicenceeExportList/gb:TradeMark where $tmGB/gb:WordMarkSpecification/gb:MarkVerbalElementText/text() contains text {$text} return <trademark><ipo>GB</ipo><text>{$tmGB/gb:WordMarkSpecification/gb:MarkVerbalElementText/text()}</text></trademark> } default return "" return <result> <total>{count($results)}</total> <trademarks> { for $result in $results return $result } </trademarks> </result> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Regards, Sebastian

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repeatedly full-text marking the same text node
by Graydon Saunders 11 May '20

11 May '20

Hello -- Is there some way to iterate full-text matches to mark up in the node every found member of a sequence of phrases? I have a use case where I have a long list of phrases which may appear in the content set; if they do appear in the content set, these should be marked. The order of the list is significant; the longest phrases should be marked first. The idea would be to iterate through the list, marking up the node with any matches. However, so far as I can tell, full text only works directly on a database node. If I try to pass the node in a function, I get "No database node" errors from attempting full-text operations. (Making a copy of the DB with a full text index, applying the changes, updating the indexes, and continuing seems possible but also inherently inefficient.) Is there a straightforward way to do this that I'm missing? Thanks! Graydon

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Stack overflow with random-number-generator
by Joe Wicentowski 11 May '20

11 May '20

Hi all, I encountered a stack overflow error with the following code, which is designed to return as many random numbers as the user requests. BaseX's error suggested, "Try tail recursion?" I think I am already using tail recursion. Changing the $n variable from 1407 to 1406 or lower avoids the error. Any number 1407 or higher triggers the error. Thank you for any hints! Joe ``` xquery version "3.1"; declare function local:get-random-numbers($how-many as xs:integer, $generator as map(*)) { if ($how-many ge 1) then ( $generator?number, local:get-random-numbers($how-many - 1, $generator?next()) ) else () }; declare function local:get-random-numbers($how-many as xs:integer) { local:get-random-numbers($how-many, random-number-generator()) }; let $n := 1407 return local:get-random-numbers($n) => count() ```

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Performance loss between version 9.2.4 and 9.3.2 when executing specific xQuery
by BIRKNER Michael 11 May '20

11 May '20

Hi, I am observing a performance loss between BaseX versions 9.2.4 (which I was using so far) and 9.3.2 (to which I updated recently) when executing an xQuery like this: --- (: Open 2 databases and get all <record>s :) let $recsFromDb1 := db:open('db1')/record let $recsFromDb2 := db:open('db2')/record (: Get distinct IDs of all records in db1 :) let $idsFromRecsInDb1 := distinct-values($recsFromDb1/exampletag[@exampleattr='id']) (: Iterate over the distinct IDs of db1 and return the records from db2 with the same ID :) for $id in $idsFromRecsInDb1 let $recFromDb2WithSameId := $recsFromDb2[exampletag[@exampleattr='id']=$id] return $recFromDb2WithSameId --- In BaseX version 9.2.4 the query executes very fast (2 - 3 seconds). In 9.3.2 I didn't wait to the end ... I aborted after several minutes because I suspected that something must be wrong. Both BaseX instances have allocated the same amount of memory (4096MB). The databases (db1 and db2) were created in the respective BaseX version from scratch and contain attribute and text indexes. They were optimized before executing the query mentioned above. All options and preferences are the same in both BaseX instances. I am using the GUI in Ubuntu 18.04. Here are some more details about the two databases: db1: - Size: 2255MB - Nodes: 97598775 - Documents: 7489 - Uptodate: true db2: - Size: 883MB - Nodes: 46317512 - Documents: 1 - Uptodate: true Does someone have an idea why there is such a difference in performance between the two BaseX versions? Thanks for any answers and hints! Best regards, Michael Mag. Michael Birkner AK Wien - Bibliothek 1040, Prinz Eugen Straße 20-22 T: +43 1 501 65 12455 F: +43 1 501 65 142455 M: +43 664 88957669 michael.birkner(a)akwien.at<mailto:Michael.BIRKNER@akwien.at> wien.arbeiterkammer.at<http://wien.arbeiterkammer.at/> Besuchen Sie uns auch auf: facebook<http://www.facebook.com/arbeiterkammer/> | twitter<https://twitter.com/Arbeiterkammer> | youtube<https://www.youtube.com/user/AKoesterreich> -------------------------------------------------- Die AK setzt sich seit 100 Jahren für Gerechtigkeit ein. Damals. Heute. Für immer. arbeiterkammer.at/100<https://arbeiterkammer.at/100><https://arbeiterkammer.at/100><https://w.ak.at/zukunftsprogramm> [https://wien.arbeiterkammer.at/ak100_maildisclaimer.png]<https://arbeiterkammer.at/100> Beachten Sie, dass Sie uns ab sofort unter einer geänderten Rufnummer erreichen. Bitte speichern Sie gleich Ihren Kontakt zur AK Wien ein unter 501 65 1, gefolgt von der gewohnten Durchwahl. Dieses Mail ist ausschließlich für die Verwendung durch die/den darin genannten AdressatInnen bestimmt und kann vertrauliche bzw rechtlich geschützte Informationen enthalten, deren Verwendung ohne Genehmigung durch den/ die AbsenderIn rechtswidrig sein kann. Falls Sie dieses Mail irrtümlich erhalten haben, informieren Sie uns bitte und löschen Sie die Nachricht. UID: ATU 16209706 I https://wien.arbeiterkammer.at/datenschutz

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Storing xml message
by Ramzi Hammouda 08 May '20

08 May '20

Hello, First, thanks for the effort you're putting it to help BaseX users. I'm Using POST method to update BaseX database, I want to insert an xml node to an existing document calastone.xml in calastone database , if the node contains '<', it returns an error " Line 6): The value of attribute "value" associated with an element type "variable" must not contain the '<' character." code: <query> <text> let $message := '<Id>CTN53</Id>' return insert nodes $message as last into doc("calastone/calastone.xml") </text> <variable name='message' value='<Id>CTN53</ID>'/> </query> the same code without '<' adds the text correctly. how to solve this problem? Note that this is a question I posted on Stackoverflow, Link<https://stackoverflow.com/questions/60456387/passing-in-xquery-with-basex-p…>. Christian Grun suggested using < and > for attributes and CDATA for text nodes. After applying that solution, the xml stored is in this form <Id>CTN53</Id> This is not what I'm looking for. Is there any other more convenient solutions to store XML messages with Rest APIs? I know PUT method works fine but it overwrites the content of the document. Thank you. P Respectons ensemble l'environnement. N'imprimez ce message que si n?cessaire. Let's respect the environment together. Only print this message if necessary.

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Send byte[] to http response ?
by Mickael Desfrenes 07 May '20

07 May '20

Hello, Probably my ignorance, but I struggle to send a byte array (byte[]) from a java module to a restxq response. Something a bit like this: return (<rest:response> <http:response status="200"> <http:header name="content-type" value="application/pdf"/> </http:response> </rest:response>, SomeJavaModule:getSomeBytes($module_instance)) I know there is a binary module in BaseX but I tried various things and couldn't get the wanted output. I could probably write the bytes in a file and then use file:read-binary() but it's something I'd like to avoid. Any clue here ? Mickaël

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9.2.1 not found in maven central
by andreas.hengsbach＠nexoma.de 07 May '20

07 May '20

Hi, is there a reason, that I can't find the current Version (9.2.1) in maven central? Thanks and best regards, Andreas

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Bug creating full-text index
by Sebastian Guerrero 06 May '20

06 May '20

Hello from Argentina!!!, thanks for the excellent software, I'm so happy learning a bit more about BaseX! Sadly I get an error trying to create a full-text index for a 51GB database: *Improper use? Potential bug? Your feedback is welcome:Contact: basex-talk(a)mailman.uni-konstanz.de <basex-talk(a)mailman.uni-konstanz.de>Version: BaseX 9.3.2Java: Oracle Corporation, 1.8.0_231OS: Windows 10, amd64Stack Trace: java.lang.NegativeArraySizeException at org.basex.index.ft.FTList.next(FTList.java:93) at org.basex.index.ft.FTBuilder.merge(FTBuilder.java:239) at org.basex.index.ft.FTBuilder.write(FTBuilder.java:147) at org.basex.index.ft.FTBuilder.build(FTBuilder.java:86) at org.basex.index.ft.FTBuilder.build(FTBuilder.java:23) at org.basex.data.DiskData.createIndex(DiskData.java:198) at org.basex.core.cmd.CreateIndex.create(CreateIndex.java:100) at org.basex.core.cmd.Optimize.optimize(Optimize.java:181) at org.basex.core.cmd.Optimize.optimize(Optimize.java:163) at org.basex.core.cmd.Optimize.optimize(Optimize.java:92) at org.basex.core.cmd.Optimize.finish(Optimize.java:82) at org.basex.core.cmd.ACreate.update(ACreate.java:96) at org.basex.core.cmd.CreateIndex.run(CreateIndex.java:64) at org.basex.core.Command.run(Command.java:257) at org.basex.core.Command.execute(Command.java:93) at org.basex.core.Command.execute(Command.java:116) at org.basex.gui.dialog.DialogProgress.lambda$execute$0(DialogProgress.java:182) at java.lang.Thread.run(Unknown Source)* I'm using BaseX GUI. Is it a known problem? any advice? Regards, Sebastian.

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Use of function-lookup in REST-XQ environment
by Mauro Mugnaini 04 May '20

04 May '20

Hi all, In order to have a "dynamic backend” implementation to REST-XQ invocations we used the fn:function-lookup() function but we are experiencing a strange behavior if the target looked-up function is an updating function that for example adds a resource to a database. Putting the provided files in the webapp folder of a fresh new BaseX latest (9.3.2) downloaded instance (adding "MIXUPDATES = true” setting in the .basex and with a database named DB already created inside) and invoking the REST function that calls directly the backend function with [1] the resource is correctly created on the database, by invoking the REST function that performs the dynamic lookup by using the fn:function-lookup() with [2] it completes without errors but the resource is not added to the DB. In our implementation the implementation modules are stored in the repo but the same behavior can be reproduced with “direct” function call as per my example. Is there any limitation in the looked-up function related to updating databases? Regards, Mauro [1] http:send-request( <http:request method="POST"> <http:body media-type="application/xml"/> </http:request>, "http://localhost:8984/store", <joe/> ) [2] http:send-request( <http:request method="POST"> <http:body media-type="application/xml"/> </http:request>, "http://localhost:8984/dyn-store", <joe/> )

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BaseX-Talk May 2020