I would need to use idbag in fluent mappings. Is it supported in fluentnhibernet?
They seemed to just have ignored it. I cannot find anything in their documentation.
There is a similar question which proposes the use of XML
It doesn't appear in the Fluent mapping
It doesn't appear it the Current NHibernate Features Not Supported In Fluent
In Entity Framework it is possible to combine fluent configuration with attribute-based configuration.
As in NHibernate both configuration approaches are different projects I guess they're not combineable, however, maybe I'm misunderstood.
Is it possible to combine both approaches in NHibernate or not?
No, you have to choose what type of configuration (or mapping) you want to do. Fluent NHibernate, Xml, Attributies. You do not need to create your configuration in a separated project, but it is a good pratice to keep the single responsability for each part of your code. I really recommend you mapping using the fluent NHibernate.
This article show each type of mapping:
http://www.davesquared.net/2008/09/nhibernate-mappings-using-xml.html
I have several projects using NH and FNH to generate the mappings (some Fluent some Automapped). There are still some bugs and missing features i need, but it seems that FNH could die because of mapping-by-code integrated into NHibernate.
Question: Contribute to FNH or to migrate the mappings to mapping-by-code or confORM and fixing problems/implementing features there?
At our office, we have been using NHibernate for 3 years now. We've been thinking about making a move to Fluent Nhibernate but never made the move. Using hbm.xml files was still the easiest to debug/alter. Two common problems of those xml files are that they are all validated during the creating of the sessionfactory and they are not refactor-safe.
Due to a bug I had to update a newer release of NHibernate (we were using NHib 2.1.2GA) and when I implemented 3.2GA we also were handed the ability to use loquacious mappings (mapping by code). I decided to use Loquacious over Fluent because I don't have a dependency to another project (Fluent) and the fact that NHibernate won't be shipped if mapping by code is broken.
Be aware though, that Loquacious mapping isn't complete either. While I was mapping everything by code, I found out basic stuff like property-ref wasn't always implemented. Thus even though it's shipped, it's not 100% complete. And while this will not come as a shocker, it has bugs. yes. really. ;-)
for more info on (reported) bugs, check out the NHibernate bug database: https://nhibernate.jira.com/browse/NH
Hope this helps.
Regards, Ted
thx to #TedOnTheNet i will continue to use and contribute to FNH, because it will take a while until mapping-by-code reaches FNH in some areas
Automapping
Fluent API tells a lot better which possibilities there are
far more verbose mappings
.Database(SQLiteConfiguration.Standard.InMemory()) is still easier to figure out than
.DataBaseIntegration(db =>
{
db.ConnectionString = ???;
db.Dialect<SQLiteDialect>();
db.Driver<???>();
});
and some features:
CompositeId and Table per Subclass
default values for legacy columns
property refs
Update: some features from hbm.xml (and FluentMapping) will not be possible at all with mapping by code:
default values for legacy columns: database column to constant value without the need for a property in the entity class with mapping by code
query only properties/collections: http://ayende.com/blog/4054/nhibernate-query-only-properties
NH 3.2 does not have anything remotely equivalent to FNH's Automapping, as far as I can tell. (For me, that would be a dealbreaker).
Edit
The FNH Automapper can deal with most of the common patterns in an object model, such as inheritance, one-to-many relationships, self-referencing, etc - without requiring any help from the programmer. So far, pure NH has not achieved this level of automation.
Also, James Gregory has publicly stated that he will continue to develop FNH, at least in the near term. (Think I saw this on the FNH Google group a few months back, but I'm not sure exactly where).
Is it possible to use NHibernate XML mapping files instead of Fluent NHibernate in S#arp Architecture framework?
Yes you can. Take a look at the Northwind sample app's NHibernate.config (the commented mapping element and the related comments)
As the title says, is it possible to get hands on the XML representation of a fluent nhibernate mapping? And if it is, can this be used directly with Hibernate for Java?
There's a section in the Fluent NHibernate wiki covering the export of the xml mapping. Section at the bottom headed 'Exporting hbm.xml mappings'
Have not tried it but don't see any reason why the mapping file shouldn't work in Hibernate with minimal modification