How to Map Two Tables To One Class in Fluent NHibernate
- by Richard Nagle
I am having a problem with fluent nhiberbate mapping two tables to one class.
I have the following database schema:
TABLE dbo.LocationName
(
LocationId INT PRIMARY KEY,
LanguageId INT PRIMARY KEY,
Name VARCHAR(200)
)
TABLE dbo.Language
(
LanguageId INT PRIMARY KEY,
Locale CHAR(5)
)
And want to build the following class definition:
public class LocationName
{
public virtual int LocationId { get; private set; }
public virtual int LanguageId { get; private set; }
public virtual string Name { get; set; }
public virtual string Locale { get; set; }
}
Here is my mapping class:
public LocalisedNameMap()
{
WithTable("LocationName");
UseCompositeId()
.WithKeyProperty(x => x.LanguageId)
.WithKeyProperty(x => x.LocationId);
Map(x => x.Name);
WithTable("Language", lang =>
{
lang.WithKeyColumn("LanguageId");
lang.Map(x => x.Locale);
});
}
The problem is with the mapping of the Locale field being from another table, and in particular that the keys between those tables don't match. Whenever I run the application with this mapping I get the following error on startup:
Foreign key
(FK7FC009CCEEA10EEE:Language
[LanguageId])) must have same number
of columns as the referenced primary
key (LocationName [LanguageId,
LocationId])
How do I tell nHibernate to map from LocationName to Language using only the LanguageId field?
