XWiki forms with database select fields

hello everybody ! I'd like to design a form with one database select field. The xwiki standard distribution provides a good basic example with the Category field within the XWiki.ArticleClass. But some additional information could be helpful : - a relational map of all the database tables involved in this application - the names and descriptions of Hibernate objects corresponding to the database objects so that I can fully undestand queries like this one : select prop.value from BaseObject as obj, StringProperty as prop where obj.className='Blog.Categories' and prop.id.id = obj.id and prop.id.name='name' (standard hibernate query for the category field) - for my current project, I intend to automatically feed this table with data updated in another database by another application software (CRM in that case). So it's crucial to know with precision what XWiki requires when managing "database select fields". Do you know about some existing developments like this one ? Thank you by advance for any information you could send to me ... Pierre Carlier pcarlier(a)repgroup.net