Hi Robert, The goal of CayenneModeler is not abstract modeling, but rather to create a binding between DB and Java. So I don't quite understand how it is useful for you if you are not writing a Cayenne application?
I'll be happy to answer the specific questions, but I am not quite sure I follow your scenario. Thanks, Andrus On Apr 9, 2013, at 7:23 PM, Robert Huber @ 7r <roberthu...@sunrise.ch> wrote: > Hello Andrus > > Thanks a lot for the new release 3B2 which was the reason to try Cayenne > Modeler again. > We currently use EOModeler for all of our modelling tasks. Having tried > Cayenne Modeler only a little bit several times, I started seriously again > with this build and your getting started guide an built the Artist - Gallery > project to see if Cayenne Modeler could now be a successor for EOModeler. > But I assume I have some general understanding problems. > > I would very much appreciate if you could demystify some of them. Thank you a > lot for your answers or hints in advance. > > Task > – In EOModeler, the task is to model an ER-Model. For example, I create an > entity, add attributes and relationships between entities. I then can add > column names and other implementation details as column width, type, … So I > make in one place the ER-Model and the mapping to the relational model. > – In Cayenne Modeler, it seems, one has to start with the implementation > side, i. e. the relational model side, and then somehow create the ER-Model? > So one is not exactly starting with modeling, but wit the implementation? > > Some Observations/Questions > → Is this the intended procedure? Why doesn't it start on the modelling side, > i. e. the defining of entities (classes) with their attributes etc.? And then > allowing to map it to the relational model. > > → The splitting between the tables and classes seems quite complicate to me, > especially with the create ObjEntity and syncing between the two «models». > May be there is a reason for this separation and syncing which I don't > recognize? > > → When creating an ObjEntity from an DBEntity (table), the name of the > ObjEntity is in plural, whereas a common naming is singular for the entity, > e. g. Artist (as it is a set), and plural for the table, e. g. artists. > Unfortunatly (for me), the ObjEntity is also plural. I found it can be > overridden, but if one presses the green C button again, an new ObjEntity in > plural is created beside the existing in singular. > > → The primary key attributes are not displayed in the ObjEntity. Why not? It > is displayed in the > > → The column name exists in ObjEntity as DbAttribute, and in the DbEntity > (table) as column name, i. e. it is in two places, but can only be edited in > the DbEntity, not in the ObjEntity > > → Naming in Cayenne Modeler its very strange for me, as many things seem > mixed. For the ERM side (P.P.S. Cheng) I would have expected terms like > entity, attribute, relationship, sub type, super type, … and for the > relational model (F. Codd) I would have expected terms like table (relation), > column, domain, … > > → If I organize the ER Diagram and Class graphs as I like, it is set to some > default (even depending on the window size) after reopening the project. If I > organize the ER Diagram, it should absolutely keep it's layout. I think this > is a necessity for larger models. > > → I miss the ability to place some sort of text box in the ER Diagram and to > give a self defined color to the entity (class) or table. > > → I did not find EOPrototypes, a great concept for applying DB types for > quickly porting a model to a new database. I really have problems if this is > not available. > > As I would primarily use the Cayenne Modeler (as we work with Servoy, we will > not use the Cayenne Framework), I am at the moment not comfortable to make > the switch from EOModeler to Cayenne Modeler. I am very much aware that > making such a tool is a lot of work and appreciate it in every way. So the > above points are not meant as a critic but a way to find out if Cayenne > Modeler could be a successor tool for us. I am also a bit unsure for what > tasks exactly Cayenne Modeler is really meant? > > Thanks and best regards, Robert > > > > _/ _/ _/ _/ _/ r. huber > _/ > _/ _/ _/ 7r gmbh > _/ _/ _/ alpenstrasse 93 > _/ _// ch-8200 schaffhausen > _/ _/ > _/ _/ tel. +41 52 624 81 15 www.seven-r.ch > > > > On 12.06.2012, at 13:17, Andrus Adamchik wrote: > >> Very happy to announce Cayenne 3.1 beta! The full announcement can be found >> here: >> >> http://cayenne.apache.org/2012/06/12/cayenne-31-beta-released.html >> >> Download is here of course: >> >> http://cayenne.apache.org/download.html >> >> A note on 3.1 documentation. The new PDF guides shipped with the download >> document all the new features, and some of the old ones. However they are >> still work in progress. I suggest still checking the PDFs, as they are the >> only source of information on the DI, configuration properties and the new >> way to start Cayenne runtime, but go back to 3.0 HTML docs whenever you find >> a gaping hole in the PDF: >> >> http://cayenne.apache.org/doc30/overview.html >> >> We should finish the docs by the time 3.1 is final. >> >> Cheers, >> Andrus > >
