Hi Julia, this looks to me as if you had hybrid data - some relational (tabular) data (addresses etc.) and other semi-structured data. If so, then think about storing the tabular data in a relational database management system (RDBMS) like Maria SQL or MS SQL Server and accessing it from within your xQueries. This is something which can be achieved very easily since the BaseX implementation accommodates adding Java code to your queries simply by dropping your jar files into the lib directory and adding a namespace declaration to the prolog of your query - it's just a snap. You can do anything you want with the relational data - insert, update, delete, and, of course, select, you can run stored procedures, and still access your XML data as easily, combine results from both sources, create great reports, and so on. Think of xQuery as a domain-specific language (DSL) for querying XML data, just as SQL is a DSL for dealing with relational data, which you can enhance according to your needs. If you need to modify only the relational part of the data, you can do this easily via the RDBMS since this is standard, and BaseX still remains the perfect choice for handling the XML part of your data. Although many RDBMSs offer also some XML and even xQuery functionality, compared to a system like BaseX this is only rudimentary. E.g. Oracle and SQL Server implement only xQuery 1.0, and even this only partially. I did something similar with BaseX and SQL Server, and - just as a proof of concept - also with Oracle. E.g., you can create SQL code with xQuery on the fly so it incorporates current context data, and pass it to some generic database access function. With JDBC, you've got the glue to connect to a wide range of database servers. I did not figure out whether you can make a database server and BaseX participate in the same distributed transaction because I had no necessity to do so; maybe Christian can tell you something more about it. Kind regards, Goetz -----Ursprüngliche Nachricht----- Von: julia.jacobson@arcor.de [mailto:julia.jacobson@arcor.de] Gesendet: Mittwoch, 29. April 2015 18:00 An: basex-talk@mailman.uni-konstanz.de Cc: heller@hellerim.de Betreff: Re: [basex-talk] Database files across multiple directories Thanks a lot for your answers so far. What I was thinking of as a use case are many small xml-Documents in many different (sub)directories that should be used together as one database, like for example one xml file for one address and address arranged into folders according to towns so one would have 9 xml files in a folder named "berlin" and 5 ones in another folder named "munich" and so on. Does BaseX create an index of these files so that I could for example query for example for persons with the same name? If I want to change something in these files, will the changes be also made in the xml documents? Kind regards, Julia