That is unfortunate.  I just reproduced the bug again, but without a
<bag>.  In ANY class that is related to User, and has a User field/
property, the wrong SQL is generated.

RelatedObj myObj = CurrentSession.Get<RelatedObj>(1);
User user = myObj.User;
Console.WriteLine(user.FName);

This generates the wrong SQL as well.  This would have the following
in RelatedObj.hbm.xml, in the <class> element.

<many-to-one name="User" column="userID" unique="true" />

I can't specify a custom loader in this case, so there is no way for
me to force the usage of vw_users.

I don't see how this can be by design.  I think this is a genuine
bug.  I specify a custom loader for the user class, and when user
objects are loaded via related entities, the loader is not used.


When I was originally faced with this Tables vs Views problem, I had 2
choices:

1) Map to the view, and override INSERT, UPDATE and DELETE behavior to
use the table instead

2) Map to the table, and override SELECT to use the view.

I went with #2, because in the NHibernate documentation, I read that
NHibernate will ignore <sql-insert> for a <class> if the <id> is
identity.  All of ours use identity, so #1 wasn't an option.


On Oct 2, 12:21 pm, "Ayende Rahien" <[EMAIL PROTECTED]> wrote:
> I _think_ you need to specify a loader for the collection as well
>
> On Thu, Oct 2, 2008 at 10:17 PM, MAMMON <[EMAIL PROTECTED]> wrote:
>
> > In my NHibernate-based ordering system project, I have a User table
> > with common fields such as FName, LName, etc.  We also have a table
> > named _tbl_AllUsers that is an import from our company's HR database
> > that has official data on our employees.  Our ordering system has to
> > accommodate users not in the HR db, but it's nice when we can keep the
> > data sync'd.  To reconcile the 2 sources of user data, we use a view,
> > vw_users, which does a COALESCE on overlapping fields.
>
> > SELECT
> >        COALESCE(userInfo.FName, hr.FName) AS FName
> >        ...
>
> > This way, we prefer data from our ordering system, but if it's not
> > their, we'll fall back on the HR database's data.
>
> > The problem with views like this is that they are read only.  If my
> > User class (User.cs and User.hbm.xml) mapped to vw_users, then I'd
> > have read only functionality, and wouldn't be able to update user
> > records.  So in User.nbm.xml, I map to the table, UserInfo, but then
> > use this in the <class> element:
>
> > <loader query-ref="qrySelectUser" />
>
> > which uses this query:
>
> >        <!-- Override the SQL for SELECT to use the view (vw_users) -->
> >        <sql-query name="qrySelectUser">
> >                <return class="User" />
> >                SELECT UserID, INTERNALID, FNAME, LNAME, MI, EMAIL,
> > PHONENUMBER,
> > TITLE, EMPLOYEEID, LoginID, LoginDomain, UserSourceType, IsVerified,
> > DateCreated, OfficeID
> >                FROM dbo.vw_users
> >                WHERE UserID = ?
> >        </sql-query>
>
> > This works like a charm.  When I load up users, I get results from the
> > view.  When I create, update, or delete users, since the User class is
> > mapped to dbo.UserInfo, that's the table that gets updated.
>
> > The problem comes in when User objects get populated some OTHER way.
> > Consider this bag in the User class:
>
> >                <bag
> >                                name="Roles"
> >                                table="User_x_Role"
> >                                access="nosetter.pascalcase-m-underscore"
> >                                inverse="false"
>
> >                        <key column="UserID" />
> >                        <many-to-many class="Role" column="RoleID" />
> >                </bag>
>
> > And then consider loading up a User object like this:
>
> > Role someRole = CurrentSession.Get<Role>(1);
> > foreach(User user in someRole.Users)
> >        Console.WriteLine(user.FName);
>
> > In this case, the User objects aren't using the <loader> in the
> > User.hbm.xml.  They get loaded from the association depicted in the
> > <bag> above, and the User objects aren't being populated from the
> > view.  The SQL generated by NHibernate (I did a trace) uses the
> > UserInfo table.  This seems inconsistent (load a user from vw_users in
> > one case, but from dbo.UserInfo in another), but perhaps it is by
> > design for some necessary reason.  Here's a cleaned up snippet of the
> > SQL from the trace:
>
> >        SELECT
> >                uxr.RoleID,
> >                uxr.UserID,
> >                ui.userID,
> >                ui.FNAME,
> >                ...
> >        FROM
> >                dbo.User_x_Role uxr
> >                left outer join dbo.UserInfo ui
> >                on uxr.UserID = ui.userID
> >        WHERE
> >                uxr.RoleID = 4
>
> > So how do I reconcile this?  I would have thought that the <loader>
> > that causes SELECTs to come from the view would still override the SQL
> > generated in this case, but it doesn't.  Do I have to create a custom
> > <loader> for the <bag> that forces the use of vw_users over
> > dbo.UserInfo?
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