we are planning to import our data that right now are in UNIMARC format, but we would appreciate input also for MARC records, into a db. We have made a transformation to get a "summary" of the data and the output is an XML file, which we would like then to have it stored in a db. Could you please tell us your experiences if you have had the chance to work on such a project? Would you suggest a relational database or a NoSQL db? Advantages and disadvantages between using Mongodb and Couchdb?