Hi Emilliano, See responses to your questions below inline:
On 13/3/07 21:41, "Emiliano Heyns" <emiliano.he...@gmail.com> wrote: > Hi, > > I've been going through the docs, and I have some questions left. The list is > pretty long, so I want to thank you guys up front for your time. As a first > project I'm thinking about doing a media server, initially for the KISS > player, the Hauppauge MediaMVP, and/or iTunes. > > Off we go: > > WebDAV > 1. The docs mention automatic extraction of metadata. How does this work? Can > new extractors be defined for custom datatypes (ogg, m4a, etc)? [Hugh] I presume you are enquiring about custom MetaData extract APIs ? Their is not documentationon how this works but their source code for those we have implemented to date are available in the source code. If you would like specific details on location I can obtain this information for you ? > 1. If the execute property is set on an vsp(x) resource it is executed when > accessed. How would I still get at the source for editing without disrupting > execution by people just visiting? [Hugh] As WebDAV uses the GET method for retrieval of a some content, generally speaking their is no way to distinguish between 'edit' and 'execute' request. To allow execute & edit capabilities a special flag is available for virtual directories 'executable=yes' , which can be set with a checkbox via the Virtuoso Conductor interface and overrides the execution permissions check-box. You can then have a two Virtual Directories one for executing the pages (i.e. URL which is exposed to public) which has the flag set and create another Virtual Directory which is complementary of the first Virtual Directory, but has the flag set to no and can be used for editing. All the active pages must not have execute bit on, which will is to allow second URL to return the source. The net effect being two URLs, one to be used for editing and the other for viewing the content. > 1. There's a mention of extending DAV by using virtual collections. How does > this work? [Hugh] This is refers to ability to create WebDAV views based on none WebDAV Data sources, with the Virtuoso ODS-Briefccase application being an example of how this has been done: http://virtuoso.openlinksw.com/wiki/main/Main/OdsBriefcase > 1. I've dabbled a bit with SQL Server 2005, which has a hard 2GB per column > limit. Does Virtuoso also have such a limit? If so, doesn't this hamper > Virtuoso's use as a (WebDAV-based) document management system? > General > > [Hugh] Virtuoso has the same 2GB limit, although this can be changed it need > be but would break backward compatibility. > > > 1. http://virtuoso.openlinksw.com/wiki/main/Main/VOSIntro > <http://virtuoso.openlinksw.com/wiki/main/Main/VOSIntro> mentioned 'hosting > non-virtuoso content'. What does this mean? How would I use it? [Hugh] This refers to content not stored in Virtuoso SQL using its virtualization features to access data from non-virtuoso sources. This also covers procy server I from of we servers via redirects etc. > 1. What kind of concurrency strategy does Virtuoso implement (MVCC, > traditional locking)? [Hugh] Virtuoso uses traditional SQL DBMS concurrency control. > 1. In an interview by Jon Udell, Kingsley Idehen mentions a drag and drop > db/form designer. Is a demo available for that? I'd truely love to see that! [Hugh] The refers to applications available as part of the OpenLink Ajax Toolkits OAT, which is includes Database and Form Designer applications amongst others enabling the graphical design of Database queries and forms. This is and Opensource offering from OpenLink which can be downloaded from the following URL: http://oat.openlinksw.com > 1. In the same interview, Kingsley likens Virtuoso to Zope. Does virtuoso > implement something like callable objects in the database, or aquisition? > Again, I'd love to hear about that! I have a bit of zope experience, and as > sweet as it is, I just can't get over how disruptive changes between even > minor versions are. Here's to hoping Virtuoso does better! [Hugh] Virtuoso¹s User Defined Types( http://docs.openlinksw.com/virtuoso/udt.html#udt) enable the calling of externally hosted functions/objects within the Virtuoso space, and is compatible across releases thus we would not expect you to have problems across releases. > 1. How would I make sure that XML documents that are inserted adhere to a > given schema? Triggers? [Hugh] Virtuoso include a built in XML Validator and associated functions that can be called for validating XML content (http://docs.openlinksw.com/virtuoso/fn_xml_validate_schema.html) > Maintenance > 1. Does Virtuoso require periodic maintenence (trx log file truncation, > vacuum)? [Hugh]When a Virtuoso checkpoint is performed the trx file will be purge as transactions are committed to the database thus providing checkpoint¹ing is enable this will be done automatically. Virtuoso does provide to Vacuum function as detailed at http://docs.openlinksw.com/virtuoso/fn_vacuum.html > 1. I'm not entirely clear on whether virtuoso-t is a single-database or a > multiple-database server. Can a single virtuoso-t host multiple databases? If > not, does that mean each database would need their own connection ports? [Hugh] Multiple database instances can be start on the same machine using the same virtuoso-t program with each instance being assigned a separate server process. > Development > 1. It is my understanding SPs can also be written in Java, Mono-supported > languages, and python. Does the debugger also work for these SPs, or only for > the ones written in PL? [Hugh] If these are create as Virtuoso User Defined types then the degugger can be used with these procedures also. > 1. Does Virtuoso use encrypted channels for database access (ODBC, JDBC, etc), > or can they be secured? [Hugh] Yesm the Virtuoso DataAccess clients do support SSL encryption > 1. Can the hosted languages access all libraries? I'm thinking about doing > some PDF reporting stuff for another project using Python PDF libs. [Hugh] Yes, all libraries will be accessible in the same way they would be if running natively. > Finally, does Virtuoso have/expect outsider contributions to the source tree? > The reason I'm asking is that this would offer more security against license > changes. No offence intended, really, but this problem has bitten me before > when I started out hacking against Ingres, which changed their license just as > I was getting somewhere at the time. A product with multiple contributers > won't easily change the license. I'm not disputing your right to change the > license at all, it's just once bitten, twice shy. > > [Hugh] We are also not in favor of open source licensing change have been > bitten by this ourselves in relation to some of the opensource database we > work with. Thus if our open source licensing was to change most probably it > would be to relax the terms, and in answer to your final question below you > are currently currently the connection libs are covered under the GPL license > but we are currently considering making them LGPL . > > Best Regards, > Hugh Williams > Professional Services > OpenLink Software > > Regarding the license, does the GPL also cover the connection libs, or are > those under the LGPL? This is not so much a problem for ODBC I expect, but the > JDBC and .Net providers get loaded into the application and thus mandate that > the application is also covered by the GPL. Which, again, is not a problem, > but it limits the other open source libraries I can use in the app. > > Thanks, > Emile > > > ------------------------------------------------------------------------- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to share your > opinions on IT & business topics through brief surveys-and earn cash > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > > _______________________________________________ > Virtuoso-users mailing list > Virtuoso-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/virtuoso-users
