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

a note on client/server interface
by Godmar Back 23 Sep '10

23 Sep '10

Should the client/server interface support the declaration of external variables? Right now, consider an XQuery such as this one (simplified form shown) declare variable *$entry* as xs:anyAtomicType external; return insert node <entry> <title>Copy of { *$entry*//atom:title/text() }</title> { *$entry*/libx:module | *$entry*/libx:package | *$entry*/libx:libapp } </entry> into $feed Suppose "entry" is an element rendered into a blob of XML of 1000 characters and markup. Before we can send above XQuery to the BaseX server, we have to replace all instances of '$entry' with the actual XML (as per the previous discussion that XQJ is deprecated and the client/server interface is the preferred way to communicate with BaseX). This means that we're sending roughly 4x the amount of data (note that $entry is used four times above), just to be able to say "$entry//atom:title/text()". This can easily lead to unexpected performance as queries become more complicated; in addition and more importantly, it makes it really tough to debug the expanded XQuery if there is a need. Why not extend the protocol so that a client can define the external variables in an XQuery first? - Godmar ps: I understand that I could work around this by introducing additional variables with let, as in let $dummy = $entry ... and then using $dummy//atom:title/text() etc. Awkward.

2 1

DeepFS: using GUI; turning whitespace chop off
by pw＠themail.co.uk 22 Sep '10

22 Sep '10

How do I turn off whitespace chopping when using the GUI to set up a DeepFS mapping? TIA

3 2

Update bug fixed
by Christian Grün 05 Sep '10

05 Sep '10

Dear all, a critical update bug has now been fixed in BaseX. In case you recently encountered any runtime exceptions with XQuery Update, or the Add/Delete commands, we recommend you to switch to the latest version 6.2.7 in the Maven repository: http://basex.org/maven/org/basex/basex/6.2.7/ Christian ___________________________ Christian Grün University of Konstanz Department of Computer & Information Science D-78457 Konstanz, Germany Tel: +49-7531-88-4449, Fax: +49-7531-88-3577 http://www.inf.uni-konstanz.de/~gruen

1 0

Beginner with PHP
by Hänzi Martina (s) 04 Sep '10

04 Sep '10

Hi I got some basic problems with the php-examples, available on the homepage. where do i have to save the php-Files? and what url do i type in to execute them? i suppose it begins with http://localhost:1984/... when i start the server and enter http://localhost:1984/BaseXData/BaseXClient.php (path where the file is saved) i only get the hourglass of the browser. i also tried with the jaxrx server on port 8984 using http://localhost:8984/basex/jax-rx but i got the same result - hourglass. both times i startet the server via the Client - Server Administrators. am i doing something wrong? Thanks for your feedback greets Martina

2 4

Out of Main Memory issues when opening a tiny database
by Sandra Maria Silcot 02 Sep '10

02 Sep '10

Hi all, This I feel sure is "pilot error"; I am messing something up in my perl script to create the db. Have a tiny collection of 6 documents 75kb when loaded. It seems to load ok but when I go to use it I am getting Out of Main Memory errors. The JVM is 4gb using -Xms and -Xmx options on the java command to start the basex server (on an 8gb VM). On reviewing the logs I can see that my client is not doing a CLOSE for the database -- yesterday's log showed 175 OPENs and only 31 closes -- OOPS!! Ok, so I start getting this: OPEN chaingang Error: Out of Main Memory. 11286.05 ms I can see in top the JVMs ram just being gobbled up rapidly until it runs out and this message appears. Yes, I know I need to fix my clients but is it possible that even when the clients session closes, somehow the database is being kept open, and eventually we run out of memory? But that doesn;t really fit with the "gobbling ram" I am seeing, unless the former situation triggers the latter. IF this is the issue, could the basex server be made to nicely close any databases open in a session when that session is closed or the pipe gets broken? # when trying to recover 2010-08-31.log:22:24:11.781 DROP DB chaingang Error: Database 'chaingang' is currently locked. Or of a db has become corrupted somehow, could it cause such message? Are there any integrity check commands on the horizon? I feel a bit nervous about these kinds of memory errors as I operate in a VSphere v4 (VMWARE) environment and my JVM monitoring skills are rudimentary -- the JVM does look like it has a nice big contiguous slab of ram to work with. Clearly something bad/silly I have done is triggering this behaviour: basex just "runs away" with ram. Any thoughts? Has the api interface changed -- my perl client dates back to late March? Sorry to be so vague. Any similarly vague clues most welcome. On a similar vien, my web interface/query controller is modperl2 under apache, which means the script sits resident in ram. I have it opening/closing a basex session on each request cycle (and am about to go check what I do when it closes!). Perhaps it would be far better to have the basex connection done in the apache initialisation stage (when apache2 launches the modperl2 modules) so the session just sits there until apache restarts. Then each request cycle should just open/close the database? I ask here as it could possibly be related to my grief above. If not my apologies for confusing the matter. I am using this Sun jdk: /opt/java/jdk1.6.0_18/bin/java. Kind of regretting not using openSolaris as my OS platform rather than Linux. I do so love its trace facilities and its a great Java platform. I'm using 64bit Linux: 2.6.27-17-server #1 SMP Fri Mar 12 02:48:52 UTC 2010 x86_64 GNU/Linux ; and BaseX 6.2.6 [Server] Best wishes all, Sandra

3 3

general question on basex database/collection design
by Sandra Maria Silcot 02 Sep '10

02 Sep '10

Hi all, Basex continues to impress. I had been under the (false) impression that a single database should contain all the data/files relevant for one particular application. I have discovered that this kind of query, which crosses/joins data across databases, works: for $c in basex:db("chaingang")//person[@key="ccc86809"] let $links := basex:db("fasdb")//linkGrp[link=$c/@target] return ($c, $links, basex:db("fasdb")//person[@key=($links//link/text())]) which gives me (as desired): <person isVdl="yes" target="ai14506" type="ccc" key="ccc86809"> <sources> <ccc id="ccc86809" n="86809"> <isVDL>yes</isVDL> <aiRef>14506</aiRef> <drupalNodeId>86809</drupalNodeId> </ccc> </sources> </person> <linkGrp id="L016612" size="3" c31a="1" dlm="1" ai="1"> <link type="dlm">dlm18216038</link> <link type="ai">ai14506</link> <link type="c31a">c31a31070390</link> </linkGrp> <person key= ... the 3 person records specified in the linkGrp. Wow! I had no idea this kind of joining across basex databases was doable. Performance is great, about 64ms. It means I can think about refactoring my rather large single db with 30 documents into far smaller and manageable chunks which become updatable (i.e. the overhead of optimizing becomes tolerable). Does anyone have any comment about this, and the pros and cons? Perhaps I should be thinking of a database for each record type/major document instead of "one big database". I can see a downside in that my queries get locked into an implementation specific syntax, but I am so pleased with what Basex fulltext querying is giving me, and the general performance and clean design, that with it being open source, I'm happy to wear this risk. Thoughts anyone? Hoping this helps someone else discover what this marvellous piece of software is capable of. Thanks again to the developers -- bravo!! Cheers, Sandra

2 3

bug in vb.net sample code for new query
by Jörg Beisiegel 30 Aug '10

30 Aug '10

Hi, I have recently discovered baseX. First of all: This is an amazing project. Thank you very much. I have tested the UI and it works great with an incredible performance. Now I want to automize xqueries against a lager list in vb.net. I have downloaded (the most recent files) from "basex - Revision 2441: /trunk/api/etc/vb" The execute function works fine but the query function throws an error during New Query creation. There appears to be a session object parameter missing: in code: Dim query As Query = session.Query(input) '...calling the Query function.... no problem Public Function Query(ByVal q As String) As Query Return New Query(Me, q) End Function ' ...then the Query function calls the Query class ' ... and here "s As Session" is required but missing. Class Query Private session As Session Private id As String Private nextItem As String ' see readme.txt Public Sub New(s As Session, query As String) session = s session.stream.WriteByte(0) session.Send(query) id = session.Receive() If Not session.Ok() Then Throw New IOException(session.Receive()) End If End Sub The query results in the following error message in the console window: " instead of 1 commands received. 8814 ms." and in the VB.net direct window I get the message "Eine Ausnahme (erste Chance) des Typs "System.IO.IOException" ist in BaseX.exe aufgetreten." Could you please help? ________________________________ [http://www.translatissimo.de/files/translatissimo_logo.png]<http://www.translatissimo.de/> Jörg Beisiegel Geschäftsführer / Managing Director Localization Consulting Desk phone: +49 7275 98933-22 mailto:joerg.beisiegel@translatissimo.de translatissimo Übersetzung und Lokalisierung GbR Bismarckstr. 19 * D-76870 Kandel * Germany http://www.translatissimo.de<http://www.translatissimo.de/> *** HINWEIS *** NOTE *** Falls die Mail Anhänge enthält, bitte Empfang bestätigen. If this mail contains attachments please confirm receipt.

3 5

bug report in basex 6.2.3 fulltext
by Sandra Maria Silcot 29 Aug '10

29 Aug '10

Hi all, The following query works: > XQUERY //b4a[shipNameNorm/text() contains text 'mount.+' using wildcards]/shipNameNorm <shipNameNorm>mountstewartelphinstone</shipNameNorm> <shipNameNorm>mountstewartelphinstone</shipNameNorm> <shipNameNorm>mountstewartelphinstone</shipNameNorm> Query executed in 22.31 ms. But with a space in the same query, the server just hangs with java using up all cpu and after a long time I get an out of memory error: 21:24:01.510 [127.0.0.1:35052] XQUERY //b4a[shipNameNorm/text() contains text 'mount .+' using wildcards]/shipNameNorm Error: Out of Main Memory. The following hints might help you: - increase Java's heap size with the flag -Xmx<size> - choose the internal XML parser in the GUI or via 'set intparse on' - deactivate the text and attribute indexes 18607.03 ms To double check, I have recreated the db and reindexed (as it had been created under an earlier version). This time I don't get an out of memory error, but this: > XQUERY //b4a[shipNameNorm/text() contains text 'mount .+' using wildcards]/shipNameNorm [XQST0054] Circular variable definition? So this still appears to me to be a bug. The db is about 1.3GB, 26 documents. and Nodes: 48959283 with Indexes: Path Summary: ON Text Index: ON Attribute Index: ON Full-Text Index: ON (wildcards) Many thanks for any guidance. Cheers, Sandra

5 6

Grouping and sorting
by reference＠gmx.de 27 Aug '10

27 Aug '10

XQuery: let $type := <type> <item id="id1"><value>3</value></item> <item id="id2"><value>3</value></item> <item id="id3"><value>6</value></item> <item id="id4"><value>5</value></item> <item id="id5"><value>5</value></item> </type> for $i in $type/item let $v := $i/value group by $v order by $v return $v Result in BaseX: <value>3</value> <value>5</value> <value>5</value> As I understand XQuery the result should be as follows: <value>3</value> <value>5</value> <value>6</value> Where ist my mistake or is it a bug in BaseX?

2 2

Question regards "add path"; does it break existing indexes?
by Sandra Maria Silcot 25 Aug '10

25 Aug '10

Hi all, Using Basex v6.2.3 jar under linux, sun jdk1.6.0_18. I have a database named 'linkdb' with a few documents and a full set of indexes built. I would like to be able to add/delete docs and simply optimise the indexes without needing to rebuild them from scratch. But I am having problems doing so. Before adding a document, the "info" command reports: Database Properties Name: linkdb Size: 29338 KB Nodes: 1085033 Height: 6 Database Creation ... Documents: 3 Whitespace Chopping: ON Entity Parsing: OFF Indexes Path Summary: ON Text Index: ON Attribute Index: ON Full-Text Index: ON All is well. I then add another document and I can access the new document via xquery, but now, even after an "optimize", "info db" reports: Database Properties Name: linkdb Size: 29414 KB Nodes: 1088588 Height: 6 Database Creation ... Documents: 4 Whitespace Chopping: ON Entity Parsing: OFF Indexes Path Summary: ON Text Index: OFF Attribute Index: OFF Full-Text Index: OFF So what has just happened to the text, attribute and fulltext indexes? The only process which seems to work is to completely rebuild them, like so: LOGIN admin OK SET pathindex on OK 0.19 ms SET textindex on OK 0.13 ms SET attrindex on OK 0.14 ms SET ftindex on OK 0.13 ms SET wildcards on OK 0.14 ms SET casesens off OK 0.13 ms SET scoring 2 OK 0.13 ms OPEN linkdb OK 0.69 ms CREATE INDEX TEXT OK 424.54 ms CREATE INDEX PATH OK 90.74 ms CREATE INDEX ATTRIBUTE OK 344.46 ms CREATE INDEX FULLTEXT OK 996.65 ms OPTIMIZE OK 1784.94 ms CLOSE OK 0.18 ms And now: Indexes Path Summary: ON Text Index: ON Attribute Index: ON Full-Text Index: ON (wildcards) In the .basex file in the home dir of the user the basex server is run as, I attempt to set global options like so: TEXTINDEX = ON ATTRINDEX = ON FTINDEX = ON WILDCARDS = ON CASESENS = OFF SCORING = 2 but this seems to be always ignored. What am I doing wrong, or is this the intended behaviour? Where does the ".basex" file need to be to take effect as a set of defaults. The behaviour is repeatable irrespective of whether I use the java client or run the commands via a perl script. Many thanks for any advice, Cheers, Sandra.

2 1

defining external variables when using BaseX in server mode
by Godmar Back 25 Aug '10

25 Aug '10

Hi, is it possible to create bindings for external variables when using BaseX's server mode? For instance, we have a query that declares: declare variable $id as xs:string external; When using XQJ, 'id' would be bound as bindNode(). In our server-based implementation, we manually substitute all occurrences of $id with its value before running the query. Obviously, this is not robust: for instance, occurrences of $id in string literals would be substituted as well, even when they should not (e.g., "$id") Is there a way to leave $id declared as external, but assign a value for it when using BaseX's server mode? - Godmar

1 0

note on BaseXClient.java
by Godmar Back 23 Aug '10

23 Aug '10

Hi, The example file BaseXClient uses an unbuffered stream to write to the socket: out = socket.getOutputStream(); void send(final String s) throws IOException { for(final byte t : s.getBytes()) out.write(t); out.write(0); } This yields extremely bad performance, especially for large queries (every single call to write will trigger a separate system call to the OS, which in turn will trigger a separate TCP segment on the wire). On a typical Ethernet, this means that 100 minimum sized packets are transmitted rather than a single packet to transmit a 100-byte query. On a different note, why is BaseXClient not part of the "official" BaseX API, or at least provided as part of the distributed .jar files in an org.basex.* package? - Godmar

3 3

exception when interrupting BaseX server
by Godmar Back 23 Aug '10

23 Aug '10

When I interrupt BaseXServer with SIGINT, I occasionally see backtraces like this one. - Godmar Starting BaseXServer on port 1985 BaseX 6.2.3 [Server] Server was started. java.io.IOException: Stream closed at sun.nio.cs.StreamEncoder.ensureOpen(StreamEncoder.java:26) at sun.nio.cs.StreamEncoder.write(StreamEncoder.java:99) at sun.nio.cs.StreamEncoder.write(StreamEncoder.java:116) at java.io.OutputStreamWriter.write(OutputStreamWriter.java:203) at java.io.Writer.write(Writer.java:140) at org.basex.server.Log.write(Log.java:76) at org.basex.server.ServerProcess.run(ServerProcess.java:178) java.io.IOException: Stream closed at sun.nio.cs.StreamEncoder.ensureOpen(StreamEncoder.java:26) at sun.nio.cs.StreamEncoder.write(StreamEncoder.java:99) at sun.nio.cs.StreamEncoder.write(StreamEncoder.java:116) at java.io.OutputStreamWriter.write(OutputStreamWriter.java:203) at java.io.Writer.write(Writer.java:140) at org.basex.server.Log.write(Log.java:76) at org.basex.server.ServerProcess.run(ServerProcess.java:178)

2 2

Bulk Loading XML documents with Add(docPath).execute(CONTEXT)
by pw＠themail.co.uk 22 Aug '10

22 Aug '10

When adding documents from a directory I get things working using a few small documents and Add(docPath).execute(CONTEXT) but when I want to add hundreds of documents (average size 1Mb) I get a memory error. I am using Jython and have -J-Xms1200M and -J-Xmx1200m should I use an iterator and only add one document at a time? [this doesn't seem to me to be the way to use Add() ] TIA Peter

2 1

how do I embed character data in XQuerys?
by Godmar Back 22 Aug '10

22 Aug '10

Hi, following Christian's insinuation we're now abandoning XQJ and are porting our application to use the ClientSession API. I'm performing a textual replacement of the external variables in my XQuery expressions before sending them to BaseX's server. I'm facing difficulties with embedding character data in the XQuery expressions that are sent to the server. Notably: xquery <c-code>if (cond) { // a C comment }</c-code> produces: Stopped at line 1, column 33: [XPST0003] Expecting "}", found "C". whereas: xquery <c-code><![CDATA[ if (cond) { // a C comment } ]]></c-code> produces: <c-code> if (cond) { // a C comment } </c-code> Is this a bug in BaseX? I thought that the use of CDATA is optional and required only if one wishes to avoid escaping <, >, & in PCDATA. If CDATA is required, I would have to convert my XML document in this way. The problem did not occur in the XQJ binding. I haven't consulted the grammar; I'm following my intuition here that XQuery should allow embedded XML fragments. Is this not so? - Godmar

3 7

Student project based on BaseX
by Antonis Thomas 22 Aug '10

22 Aug '10

Hello all, we are two master students at the university of Utrecht. We have a DB Architecture class that includes a small project (15%*7.5 ECTS= 1.125 ECTS). So, BaseX looks like a good chance to work on such a project. Our idea so far is based on some benchmarking experiments and small summary on how it works (maybe its relation with Monet) including any experiments we run (5-6 pages). Do you have anything better for us to do (maybe something you can get advantage of yourselves) or any guidelines/hints/whatever? Take into account that out time limit is approximately a week (full-time) and that we cannot do more work that what deserves 2.25ECTS for the 2 of us. I look forward to an answer (so we can decide and start working -the deadline is 9/7-. Best regards, -- Antonis Thomas Information & Computing Sciences Utrecht University Utrecht, The Netherlands

2 13

how to separate multiple results when using BaseX's client/server interface
by Godmar Back 19 Aug '10

19 Aug '10

Hi, when I use the client/server interface and run a query that returns multiple nodes, BaseX appears to return the results concatenated (and, somewhat oddly, with interspersed newlines). For instance, xquery declare namespace atom='http://www.w3.org/2005/Atom'; doc('myfeed')//atom:title returns: <title xmlns="http://www.w3.org/2005/Atom">First Title</title> <title xmlns="http://www.w3.org/2005/Atom">Second Title</title> <title xmlns="http://www.w3.org/2005/Atom">Third Title</title> .... Does anybody happen to know how to parse those into separate XML documents in Java? (Short of preprocessing the XML to find the matching end tag for each element?) For background, classes such as javax.xml.parsers.DocumentBuilder can only parse one document at a time, and throw an error if the input source contains multiple documents/fragments. Alternatively, would it make sense for BaseX to support returning results one by one (perhaps using a cursor approach) to ease the client's task of parsing the returned XML? - Godmar

3 3

Re: [basex-talk] Error while creating an attribute index with the latest from SVN
by Huib Verweij 19 Aug '10

19 Aug '10

Hi Christian, Op 19 aug 2010, om 13:18 heeft Christian Grün het volgende geschreven: > The stack trace indicates that the merge of several temporary index > instances causes problems. Regarding the SVN history, the current > index builder shouldn't have been changed that much since… 6.1.8? As a > shortcut, it might help to give the JVM different -Xmx values; 1gb > should be completely more than enough for 780 mb of input data. In the > GUI, you should be able to observe how much RAM is actually used > during index construction. That was it. 1Gb didn't work, but 2Gb was enough to get it done in about 50 seconds. > >> I don't get anything else, if there's something I can do to debug it let me know. > > It might help if you could provide us with the original data (which > will of course be handled confidentially). It might take some time, > however, as I'm currently busy writing my thesis… I can't supply you with the original data I'm afraid. That would breach my contract with the MPI. Anyway, thanks for your help again and good luck with the thesis. Huib.

1 0

How is transaction supported in BaseX?
by 汤力丞 18 Aug '10

18 Aug '10

Recently I choosed BaseX as our cybermarketing data store. The most appealing feature for us is ACID transaction support as BaseX claims while eXist supports only invisible transactions limited to crash recovery. But I failed to find any example or command related such as ROLLBACK or COMMIT. So how can I fully utilize this important feature? Thanks! Best regards, Michael Tang

2 1

Re: [basex-talk] BaseX [NOT PROTECTIVELY MARKED]
by Christian Grün 18 Aug '10

18 Aug '10

Hi Peter (cc to the mailing list), the following page might interesting for you, on which we've compiled some statistics on created databases: http://basex.org/documents Reg. number of documents and single doc size: the number depends on various meta data such as the number of XML nodes in the document. As you can see on the quoted page, we've added 10 Mio. documents of the CoPhIR collection in one database, and one document with 421 GB. As soon as one database gets too large, several databases can be created and accessed by a single XQuery. Hope this helps, Christian On Wed, Aug 18, 2010 at 2:59 PM, <Peter.Winstanley(a)scotland.gsi.gov.uk> wrote: > Classification: NOT PROTECTIVELY MARKED > > Hi Christian > > I've just started looking at BaseX and would appreciate some pointers to > performance information. My obvious expectation for comparisons would be > with eXist and MarkLogic. > > I was wondering if you had any information on the maximum numbers of > documents that BaseX can handle, and also the maximum size of a single > document that could be practically handled (here I'm thinking about > multi-dimensional data 'cubes') > > Kind regards > > Peter > > Dr Peter Winstanley > ISIS: Information Management Unit > The Scottish Government > 5 Atlantic Quay > 150 Broomielaw > Glasgow G2 8LU > Scotland > 0300 244 6895

1 0

BaseX as persistence layer
by chas＠munat.com 18 Aug '10

18 Aug '10

I'm trying to use BaseX as a persistence layer in a project (together with XStream). I have a few questions and I'm not having any luck with the documentation. I've gotten pretty far. I have a User object (simplified for this example) with an id (UUID), a username (String), and a password (String). XStream turns this into: <User> <id>98bdb472-97ad-4de1-b1c6-a482d7f06d94</id> <username>Chas</username> <password>secret</password> </User> I've created a DB called "db" (clever, huh?): new CreateDB("cop", "<blog><users/></blog>").execute(context) QUESTION: If I rerun the above, will it overwrite the DB if it already exists, or will it just open the existing DB? Can't find anything in the API about that. Then I save my User like this: new XQuery("insert node" + chas + " into /blog/users").execute(context) where chas is the above XML. This works great! When I need to reinflate the object, I just do: chas = new XQuery(""" for $x in /forum/users/User where $x/username="Chas" return $x """).execute(context) Then I use XStream to reinflate the object. Any suggestions for improvement? So now the problem. I need to update this object in the database. The simplest way is just to update the whole object. So I change my username and use XStream to create the new XML: <User> <id>98bdb472-97ad-4de1-b1c6-a482d7f06d94</id> <username>Charles</username> <password>secret</password> </User> I read that one must use put() to export the changes, but maybe I'm misunderstanding this. I'm have this: for $x in /forum/users/User where $x/username="Chas" return replace node $x with " + chas This and seems to work, but then when I try to delete the node thus: for $x in /forum/users/User where $x/password="secret" return delete nodes $x It does not work. What am I missing? Thanks for any help. If this thing works, I'm happy to open it up so others can work on it, too. Chas.

5 8

Schwerer Bug von Namespace!
by Truong An Nguyen 18 Aug '10

18 Aug '10

Hallo, ich verwende im Moment die BaseX 6.2.4. Wieso sind die Namespaces unterschiedlich behandelt in zwei folgenden Situationen: + Fall 1: Die Datenbank wurden erzeugt von einem ganzen Ordner: Create Database c:\Root declare namespace ns='http://iso.org/OTX'; collection('Root')/ns:otx/ns:procedures/ns:procedure/ns:realisation Die Ergbenisse sind: "<realisation xmlns:hmi="http://iso.org/OTX/StandardInterface/HMI" xmlns:diag="http://iso.org/OTX/StandardInterface/DiagCom" xmlns:env="http://iso.org/OTX/StandardInterface/Environment"> + Fall 2: Die gleiche Datei wurde zu einer leeren Collection hinzugefügt. Create Database Empty Add TO c:\Root c:\Root\file.xml Dann funktioniert die Abfrage im Fall 1 nicht mehr. Wenn ich die Namespace von procedures, procedure und realisation wie folgend wegmache, funktioniert es. declare namespace ns='http://iso.org/OTX'; collection('Root')/ns:otx/procedures/procedure/realisation Aber alle Namespace-Informationen im Ergebnis sind auch weg. Ich bekomme nur "<realisation> ...." Fall 2 ist mir sehr wichtig. Könntet ihr bitte diesen Bug beheben? Vielen Dank Gruß, An

1 0

Q.: safety/concurrent access to BaseX database
by Godmar Back 17 Aug '10

17 Aug '10

Hi, I just wanted to confirm some assumptions about the safety of accessing a single BaseX instance from multiple JVMs, or from multiple org.basex.api.xqj.BXQDataSource class instances loaded by different class loaders in the same VM. Am I correct that it is safe to access the same database via XQJ in such situations? By "safety," I mean that a) the database protects its internal data structures in the face of such concurrency and b) there is a serializable schedule of individual XQJ executions that produces the final database state. Is this true? Please note that I'm not asking for transactions across multiple XQJ executions here. - Godmar

2 6

BaseX namespace bugs und kein Ende
by Godmar Back 17 Aug '10

17 Aug '10

Here's a test case: http://top.cs.vt.edu/~gback/bx/b622/TestNS.java We insert a node, BaseX ignores its namespace and produces wrong XML. - Godmar

1 0

Error while creating an attribute index with the latest from SVN
by Huib Verweij 17 Aug '10

17 Aug '10

Hi, I am using the latest version from the SVN repo. It works mostly fine, but it reported that an attribute index wasn't present. Trying to add the Attribute index threw up this error. Possible bug? Feedback is welcome: basex-talk(a)mailman.uni-konstanz.de BaseX 6.2.4: java.lang.ArrayIndexOutOfBoundsException: 0 org.basex.util.Num.size(Num.java:97) org.basex.index.ValueBuilder.write(ValueBuilder.java:193) org.basex.index.ValueBuilder.merge(ValueBuilder.java:143) org.basex.index.ValueBuilder.build(ValueBuilder.java:92) org.basex.index.ValueBuilder.build(ValueBuilder.java:40) org.basex.core.cmd.ACreate.index(ACreate.java:121) org.basex.core.cmd.CreateIndex.run(CreateIndex.java:63) org.basex.core.Command.run(Command.java:234) org.basex.core.Command.exec(Command.java:217) org.basex.core.Command.execute(Command.java:65) org.basex.core.Command.execute(Command.java:77) org.basex.gui.GUICommands$50.run(GUICommands.java:963) I tried exporting everything and reloading it again, but strangely enough it couldn't parse one file that oXygen could parse without problems. Anyway, after all documents except one were reloaded into the db it reported a missing attribute index. I tried to add it again, but I got the same error again. I know I'm not using a release version, I'm not complaining, just reporting. Regards, Huib.

2 1

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

BaseX-Talk