How can I map these Entities using mapping-by-code:
public class Foo
{
public virtual IDictionary<Bar, string> Bars { get; set; }
}
public class Bar
{
public virtual int Id { get; set; }
public virtual string Name { get; set; }
}
I found this thread, but it does not map an entity, only simple types. I tried many mappings, including automapping:
Map(x => x.Bars,
m =>
{
m.Key(k => k.NotNullable(true));
m.Cascade(Cascade.All);
},
But most of them throw these two errors:
Foreign key (Bars [idx])) must have same number of columns as the referenced primary key (Bars [FooId, idx]).
An association from the table FoosToStrings refers to an unmapped class: System.String.
Any help will be highly appreciated. Thanks. :)
i think this should work
Map(x => x.Bars,
entryMap => entryMap.Key(k => k.Column("foo_id")),
keymap => keymap.ManyToMany(m => m.Column("bar_Id")),
elementMap => elementMap.Element(m => m.Column("value")));
Related
I have the following classes:
public class Track
{
public virtual int Id { get; set; }
public virtual Track MainMix { get; set; }
public virtual IEnumerable<Track> SubMixes { get; set; }
public virtual IList<FileVersion> Files { get; set; }
}
public class FileVersion
{
public virtual int Id { get; set; }
public virtual Track Track { get; set; }
}
And the following mappings:
public class TrackMap : ClassMap<Track>
{
public TrackMap()
{
Id(x=>x.Id);
References(x => x.MainMix);
HasMany(x => x.SubMixes)
.Inverse()
.Cascade.All()
.KeyColumn("MainMix_id");
HasMany(a => a.Files)
.Access.CamelCaseField(Prefix.Underscore)
.Cascade.All();
}
}
public class FileVersionMap : ClassMap<FileVersion>
{
public FileVersionMap()
{
Id(x => x.Id);
References(x => x.Track);
}
}
There is omitted code for the sake of simplicity. The Track table has a "MainMix_id" column that is a self referencing column for a parent/child relationship among Track records.
When I try to fetch a track from the database the NHProfiler tells me that Nhibernate tries to fetch the fileversions of that track with the following query:
SELECT files0_.MainMix_id as MainMix9_1_,
files0_.Id as Id1_,
files0_.Id as Id9_0_,
files0_.Track_id as Track8_9_0_
FROM [FileVersion] files0_
WHERE files0_.MainMix_id = 3 /* #p0 */
It seems like it has confused the parent id column of the Track table with its primary key column. When I remove References(x => x.MainMix) from the Track mapping the query is correct, but I don't have the parent track record returned.
Let me know if I can clarify this any more and thanks in advance for your help!
Does this make a difference?
TrackMap :
References(x => x.MainMix).Column("MainMix_id");
FileVersionMap :
References(x => x.Track).Column("Track_id");
I have an pretty big database and I have to map two entities using NHibernate 3.3.1 byCode mapping (please take in account that I'm not using FluentNHibernate, but built-in mappings)
Entities are in a many to many relationship through and unique key, not primary key.
Here are my examples
public class Achievable : Entity
{
public Achievable()
{
Uniqueidentifier = Guid.NewGuid();
}
public virtual string Name { get; set; }
public virtual Guid Uniqueidentifier { get; set; }
public virtual IList<Kitting> Kittings { get; set; }
}
public class Kitting : Entity
{
public virtual string Name { get; set; }
public virtual IList<Achievable> Achievables { get; set; }
}
So I have to link Achievable table to Kitting using third table AchievableKittings through Uniqueidentifier property
I've written the following mapping classes :
public class AchievableMap : ClassMapping<Achievable>
{
public AchievableMap()
{
Property(x => x.Name);
Property(x => x.Uniqueidentifier, m =>
{
m.Unique(true);
m.NotNullable(true);
});
Bag(x => x.Kittings, m =>
{
m.Table("AchievableKittings");
m.Cascade(Cascade.Persist);
m.Inverse(false);
m.Key(k =>
{
k.PropertyRef(x => x.Uniqueidentifier);
k.Column("aUniqueindentifier");
k.ForeignKey("FK_Achievable_uniqueidentifier");
});
}, r => r.ManyToMany(m =>
{
m.Column("kittingId");
m.ForeignKey("FK_Kitting_kittingId");
}));
}
}
public class KittingMap : ClassMapping<Kitting>
{
public KittingMap()
{
Property(x => x.Name);
Bag(x => x.Achievables, m =>
{
m.Table("AchievableKittings");
m.Inverse(true);
m.Key(k =>
{
k.Column("kittingId");
k.ForeignKey("FK_Kitting_kittingId");
});
}, r => r.ManyToMany(m =>
{
m.Column("aUniqueindentifier");
m.ForeignKey("FK_Achievable_uniqueidentifier");
}));
}
}
It seams that NHibernate ignore k.PropertyRef(x => x.Uniqueidentifier) statement. My Primary keys are bigint generated by identity. Now when Nhiebrnate tries to create the db its create the FK key for AchievableKittings to primaryKey of achievable, but not property-ref Uniqueidentifier
alter table AchievableKittings
add constraint FK_Achievable_uniqueidentifier
foreign key (aUniqueindentifier)
references Achievable
and of course its throws an exception:
Column 'Achievable.AchievableId' is not the same data type as referencing column 'AchievableKittings.aUniqueindentifier' in foreign key 'FK_Achievable_uniqueidentifier'.
Using FluentNhibernate is was able to map this in a right way. Unfortunately I can not use FluentNhibernate in current project.
So could some one help me with this issue.
I do it like this and always use sets
Set(x => x.Users, d =>
{
d.Schema("dbo");
d.Inverse(false);
d.Access(Accessor.Property);
d.Table("UsersRoles");
d.Key(c => c.Column("RoleId"));
}, r => r.ManyToMany(c => { c.Class(typeof(User)); c.Column(n => n.Name("UserId")); }));
Using NHibernate 3.2 ByCode configuration, I am attempting to map the following hierarchical entity:
public class BusinessType
{
public virtual Guid BusinessTypeId { get; set; }
public virtual Guid? ParentBusinessTypeId { get; set; }
public virtual String BusinessTypeName { get; set; }
public virtual ICollection<BusinessType> Children { get; set; }
}
with this ClassMapping:
public class BusinessTypeMapper : ClassMapping<BusinessType>
{
public BusinessTypeMapper()
{
Id(x => x.BusinessTypeId, x => x.Type(new GuidType()));
Property(x => x.ParentBusinessTypeId, x => x.Type(new GuidType()));
Property(x => x.BusinessTypeName);
Set(x => x.Children,
cm =>
{
// This works, but there is an ugly string in here
cm.Key(y => y.Column("ParentBusinessTypeId"));
cm.Inverse(true);
cm.OrderBy(bt => bt.BusinessTypeName);
cm.Lazy(CollectionLazy.NoLazy);
},
m => m.OneToMany());
}
}
This works fine, but I'd rather be able to specify the key of the relation using a lambda so that refactoring works. This seems to be available, as follows:
public class BusinessTypeMapper : ClassMapping<BusinessType>
{
public BusinessTypeMapper()
{
Id(x => x.BusinessTypeId, x => x.Type(new GuidType()));
Property(x => x.ParentBusinessTypeId, x => x.Type(new GuidType()));
Property(x => x.BusinessTypeName);
Set(x => x.Children,
cm =>
{
// This compiles and runs, but generates some other column
cm.Key(y => y.PropertyRef(bt => bt.ParentBusinessTypeId));
cm.Inverse(true);
cm.OrderBy(bt => bt.BusinessTypeName);
cm.Lazy(CollectionLazy.NoLazy);
},
m => m.OneToMany());
}
}
The problem is that this causes NHibernate to generate a column called businesstype_key, ignoring the already-configured ParentBusinessTypeId. Is there any way to make NHibernate use a lambda to specify the relation, rather than a string?
I never need to navigate from children to parents, only from parents
to children, so I hadn't thought it necessary
then remove public virtual Guid? ParentBusinessTypeId { get; set; } completly. NH will then only create "businesstype_key" (convention) and no "ParentBusinessTypeId". if you want to change that then you have to specify your prefered columnname with cm.Key(y => y.Column("yourpreferredColumnName"));
I have couple of classes and want to map them correctly to database:
public class A
{
public virtual Guid Id { get; private set; }
public virtual ComponentClass Component { get; set; }
}
public class ComponentClass
{
public virtual IList<B> Elements { get;set; }
}
public class B
{
public virtual Guid Id { get; private set; }
public virtual DateTime Time { get; set; }
}
I map them using fluent mappings like that:
public class AMap : ClassMap<A>
{
public A() {
Id(x => x.Id);
Component(x => x.Component,
c => c.HasMany(x => x.Elements).Inverse().Cascade.All());
}
}
public class BMap : ClassMap<B>
{
public B() {
Id(x => x.Id);
Map(x => x.Time);
}
}
When I save my entity, I have class A mapped to one table and class B to another as expected.
But I have nulls in Component_id column.
Can you tell me what am I missing here?
I believe Components are supposed to be in the same table , as clearly stated in Ayende's blog post, as they serve only to make the data better represented as an object model. Be sure to read through his blog, it's probably one of the best nHibernate resources out there.
Ok, I've resolved my problem - I can use Id of my "parent" class. So the component mapping will become:
public class AMap : ClassMap<A>
{
public A() {
Id(x => x.Id);
Component(x => x.Component,
c => c.HasMany(x => x.Elements).Cascade.All().Column("Id"));
}
}
So obvious as I look at it now ... but It took me an hour.
If you have a one-to-many association direct to a collection of components (ie. without the ComponentClass wrapper as per the question) then you can map it directly:
HasMany(x => x.Elements)
.AsSet()
.Table("ElementTable")
.KeyColumn("KeyColumn")
.Cascade.All()
.Component(x =>
{
x.Map(c => c.Id);
x.Map(c => c.Time);
})
.LazyLoad();
Using fluentnhibernate i am having a problem with the link table insertion.
Here is my entities
public partial class Item
{
public virtual int Id
{
get;
set;
}
public virtual string Description
{
get;
set;
}
public virtual IList<Category> Categories
{
get;
set;
}
}
public partial class Category
{
public virtual int Id
{
get;
set;
}
public virtual string Name
{
get;
set;
}
public virtual string Description
{
get;
set;
}
public virtual IList<Item> Items
{
get;
set;
}
}
Here is my mappings.
public class ItemMapping : ClassMap<Item>
{
public ItemMapping()
{
Table("Item");
Schema("dbo");
Id(x => x.Id);
Map(x => x.Description);
HasManyToMany(x => x.Categories)
.ChildKeyColumn("Item_id")
.ParentKeyColumn("Category_id")
.Table("CategoriesToItems")
.AsSet();
}
}
public class CategoryMapping : ClassMap<Category>
{
public CategoryMapping()
{
Table("Category");
Schema("dbo");
Id(x => x.Id);
Map(x => x.Description);
Map(x => x.Name);
HasManyToMany(x => x.Items)
.ChildKeyColumn("Category_id")
.ParentKeyColumn("Item_id")
.Table("CategoriesToItems")
.AsSet();
}
}
Here is how i add it to collection in my mvc page
var category = CategoryTask.Query(x => x.Id == post.Category).FirstOrDefault();
var item = new Item
{
Categories = new List<Category> { category },
Tags = tags
};
ItemTasks.Save(item);
My question is why it doesnt add the relations in my link table "CategoriesToItems". The table is already in the database with Category_Id (FK, int, not null) and Item_Id (FK, int, not null).
Where is the problem? why it doesnt add it to relation table?
It's hard to say what's really wrong when we can't see what your ItemTasks.Save does under the covers. Are you wrapping your save in a transaction? If not, you should be.
You should call Session.Flush() just before the transaction.Commit() as well.
I am not certain if the problem has been solved, but it looks similar to my problem (fluentnhibernate hasmanytomany same identifier exception).
Also, it looks like your parent and child key columns are backward.