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

Parallel execution
by Klāvs Priedītis 02 Mar '16

02 Mar '16

Hello, BaseX team and community! Disclosure: I am not yet an expert on these issues and I have not fully studied the specs of XQuery. Now that Async Module is incorporated, I am wondering about some basic properties of xquery. Example: ```xquery for $i in 1 to 10 return fetch:text("http://example.com/magic-story/for-number/" || $i) ``` It feels to me that the xquery processor is broken if it cannot figure out on its own that the fetch can be done in parallel. Why does this not work out of the box? Can it work out of the box? Wouldn't it be able to do this in parallel if a flag `can-be-optimized-for-parallel-execution` was defined for the `fetch:text`? -- Veiksmi vēlot, Klāvs Priedītis

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BaseX in a Multi-User VM
by Cecil Tarasoff 02 Mar '16

02 Mar '16

Hello, The environment that I am using BaseX GUI in is on a Virtual Workstation that is shared by multiple users. I am finding that my preferences end up being global and any user of BaseX on this workstation seems to be using the preferences that I have defined. Is it possible to install BaseX onto a multi-user workstation so that we each have our own config and repositories and keep our own data private? Thanks. Cec Tarasoff.

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client:query freeze
by Strasser Pablo 01 Mar '16

01 Mar '16

Hi, Thanks for your great software. Using basex 8.4. I found the following strange behaviour in client:query call. Calling a repository function which use client:query to call another repository function freeze the basex server if done on the server. The only way to stop the server is with a kill -9. However using the standalone client it work normally. Trying to reproduce this problem I managed to get a similar problem using 2 repository test and test2. Where the first repo use a function of the second. Do you have some idea how to investigate this problem? Is it a bug? Code of test: module namespace m = 'http://strasser-family.ch/test'; declare variable $m:c := client:connect('localhost', 1984, 'admin', 'admin'); declare function m:test(){ client:query($m:c, "import module namespace m = 'http://strasser-family.ch/test2';m:test()") }; Code of test2: module namespace m = 'http://strasser-family.ch/test2'; declare function m:test() { <dummy/> }; usage code: import module namespace m = 'http://strasser-family.ch/test'; m:test() Have a nice evening. Pablo

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out of main memory
by michele.greco2＠email.it 01 Mar '16

01 Mar '16

Hi, i get the error "out of main memory", when i run my query on a collection in basex gui. How can i fix? How can i increase my memory? Regards  Michele -- ZE-Light e ZE-Pro: servizi zimbra per caselle con dominio email.it, per tutti i dettagli Clicca qui http://posta.email.it/caselle-di-posta-z-email-it/?utm_campaign=email_Zimbr… Sponsor: Soluzioni di email hosting per tutte le esigenze: dalle caselle gratuite a quelle professionali su piattaforma Zimbra, da quelle su proprio dominio a quelle certificate PEC. Confronta le soluzioni Clicca qui: http://adv.email.it/cgi-bin/foclick.cgi?mid=13326&d=1-3

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About user names
by France Baril 29 Feb '16

29 Feb '16

Hi, I'm looking at the user module because I want to implement a login feature on one of my web application. More specifically, I'm looking at the restrictions: http://docs.basex.org/wiki/Valid_Names#Valid_Names For web applications, it is very usual for people to use an email as a username. The restriction on the period character is very annoying in that regard. I understand why it's a restriction on database names, but for user names it creates a limit on the ability for less frequent users to access the site. Most people remember which email they used or have only 2 or 3 to try. Passwords are saved in keychains. However, remembering a username... pfff! Is there any way that the restrictions on user names could be adapted to allow for characters that are valid for an email address in the near future? -- France Baril Architecte documentaire / Documentation architect france.baril(a)architextus.com

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Re: [basex-talk] basex-xqj source?
by Kendall Shaw 29 Feb '16

29 Feb '16

Oh, it’s here: http://xqj.net/basex/download.jsp Kendall From: <basex-talk-bounces(a)mailman.uni-konstanz.de<mailto:basex-talk-bounces@mailman.uni-konstanz.de>> on behalf of Kendall Shaw <kendall.shaw(a)workday.com<mailto:kendall.shaw@workday.com>> Date: Monday, February 22, 2016 at 3:27 PM To: "basex-talk(a)mailman.uni-konstanz.de<mailto:basex-talk@mailman.uni-konstanz.de>" <basex-talk(a)mailman.uni-konstanz.de<mailto:basex-talk@mailman.uni-konstanz.de>> Subject: [basex-talk] basex-xqj source? Hi, Where can I find source code for the basex xqj implementation? I want to see what it is doing. Thanks, Kendall

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Re: [basex-talk] Add docments and retrieve results using java
by Kendall Shaw 23 Feb '16

23 Feb '16

It looks like the basex-test projects shows how to do what I want. Using QueryProcessor and the Xdm classes. Kendall From: <basex-talk-bounces(a)mailman.uni-konstanz.de<mailto:basex-talk-bounces@mailman.uni-konstanz.de>> on behalf of Kendall Shaw <kendall.shaw(a)workday.com<mailto:kendall.shaw@workday.com>> Date: Monday, February 22, 2016 at 4:56 PM To: "basex-talk(a)mailman.uni-konstanz.de<mailto:basex-talk@mailman.uni-konstanz.de>" <basex-talk(a)mailman.uni-konstanz.de<mailto:basex-talk@mailman.uni-konstanz.de>> Subject: [basex-talk] Add docments and retrieve results using java How can I incrementally import XML documents into the database, using java? And, how can I incrementally retrieve query results and XML documents from the database, using java? Either I am missing it, or XQJ does not allow you to store data into a database. Should I use xmldb API? Or, should I use the native API? If so how do I incrementally read and write, instead of loading everything into a string or reading and writing to/from files? Kendall

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Add docments and retrieve results using java
by Kendall Shaw 23 Feb '16

23 Feb '16

How can I incrementally import XML documents into the database, using java? And, how can I incrementally retrieve query results and XML documents from the database, using java? Either I am missing it, or XQJ does not allow you to store data into a database. Should I use xmldb API? Or, should I use the native API? If so how do I incrementally read and write, instead of loading everything into a string or reading and writing to/from files? Kendall

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basex-xqj source?
by Kendall Shaw 23 Feb '16

23 Feb '16

Hi, Where can I find source code for the basex xqj implementation? I want to see what it is doing. Thanks, Kendall

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Benchmarking and caching in BaseX
by Bram Vanroy | KU Leuven 21 Feb '16

21 Feb '16

Dear all My name is Bram Vanroy, and I am an intern at the Centre for Computational Linguistics (CCL; http://www.arts.kuleuven.be/ling/ccl [Dutch]) at the University of Leuven. My supervisor, Vincent Vandeghinste, has had contact with this mailing list some time ago, more specifically with Dirk Kirsten. My intership is titled "Fine-tuning the GrETEL Treebank Query Engine". GrETEL stands for Greedy Extraction of Trees for Empirical Linguistics; available at http://gretel.ccl.kuleuven.be/gretel-2.0/. Its goal is to provide users with a fast, user-friendly on-line tool to search through text corpora backed by treebanks. Accessibility is an important point for us: users do not need to be proficient with any programming languages, strict formalisms, or treebank specific annotations; every query can be executed by using an intuitive graphical interface. More advanced users can use XPath to write the representation of the syntactic structure that they are looking for. BaseX is our tool of choice as a database for our corpora in XML format. Initially, GrETEL provided access to smaller corpora such as CGN (9 million words) and Lassy Small (1 million words). We would like to expand the searchable corpora by also making the full Sonar corpus available (500 million words). This is already partially possible in GrETEL 2.0 but due to efficiency reasons, capabilities are restricted: users can only search in one component at a time, and the largest component in the corpus is not available due to its size (15 million sentences). We have applied these restrictions because the search time for the whole corpus was too long, which in turn would decrease the user-friendliness of the tool drastically. Steps have already been taken to improve search times in larger corpora. (See "Making a Large Treebank Searchable Online. The SoNaR Case." by Vincent Vandeghinste, and Liesbeth Augustinus; http://nederbooms.ccl.kuleuven.be/documentation/LREC2014-GrETELSoNaR.pdf.) To spare you the effort to go through the whole article, I hereby quote the most relevant citation from that article for this email: The general idea behind our approach is to restrict the search space by splitting up the data in many small databases, allowing for faster retrieval of syntactic structures. We organise the data in databases that contain all bottom-up subtrees for which the two top levels (i.e. the root and its children) adhere to the same syntactic pattern. When querying the database for certain syntactic constructions, we know on which databases we have to apply the XPath query which would otherwise have to be applied on the whole data set. We have called this method GrETEL Indexing (GrInd). (p. 17) So to optimise searching, the data has been pulled apart - in a sense - which would make the search space smaller and subsequently the search time shorter. In the future we would like to apply this technique on parallel corpora as well. We have not tested yet what influence this change has made to query time which is what I am going to find out during my internship. I have already analysed the XPath queries that users have made since GrETEL saw its first user and found that the queries are ten embedded levels deep at the most, but most are between one and five. The amount of nodes per query varies between one and 24, but most searches are for structures that contain between one and eight nodes. Based on this information, I am writing example XPaths that I am going to pull through BaseX as a sort of benchmark. I can then compare the query speeds between the split-up corpus, and the regular one. The problem that I have encountered is that BaseX seems to cache very efficiently. Obviously this is not a problem on production websites but for benchmarking it may not be ideal. My first question to you, then, is: is it possible to disable caching when testing queries locally? And how exactly does BaseX handle the caching? Or more specifically, if I enter a query: what is cached, and for how long? This information me be useful to analyse our logs with. If you have any feedback on GrETEL, or the new approach of GrInding, or if you have any ideas to improve search time for large corpora - I would love to hear from you, you can contact me via this email address or on LinkedIn. I reply to each email as extensively as possible. Thank you in advance, Kind regards Bram Vanroy https://be.linkedin.com/in/bramvanroy

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