Fluent NHibernate mapping

Question

I have these classes:

public class Entity
{
  public virtual Guid Id { get; set; }
  public virtual string EntityName { get; set; }
  public virtual IDictionary<string, Property> { get; set; }
  // ...
}

public class Property
{
  public virtual int? IntValue { get; set; }
  public virtual decimal? DecimalValue { get; set; }
}

Is it possible to create Fluent NHibernate mappings so that executing the resulting schema will give these tables:

[Entities]
* Id : UNIQUEIDENTIFIER NOT NULL
* EntityName : NVARCHAR(50) NOT NULL
with a clustered index on "Id"

[Properties]
* EntityId : UNIQUEIDENTIFIER NOT NULL
* PropertyName : VARCHAR(50) NOT NULL
* IntValue : INT NULL
* DecimalValue : DECIMAL(12,6) NULL
with a clustered index on "EntityId" and "PropertyName"

Or do I need to change my classes?

An answer more verbose than yes/no will be much appreciated :)

Answer 1

Here's the mapping that I have come up with:

public sealed class EntityMap : ClassMap<Entity>
{
    public EntityMap()
    {
        Table("Entities");

        Id(c => c.Id);
        Map(c => c.EntityName).CustomSqlType("nvarchar(50)").Not.Nullable();

        HasMany(c => c.Properties)
            .KeyColumn("EntityId")
            .AsMap<string>("PropertyName")
            .Component(part =>
            {
                part.Map(x => x.IntValue);
                part.Map(x => x.DecimalValue).Precision(12).Scale(6);
            });
    }
}

Schema generation yields this:

create table Entities (
   Id UNIQUEIDENTIFIER not null,
   EntityName nvarchar(50) not null,
   primary key (Id)
)

create table Properties (
   EntityId UNIQUEIDENTIFIER not null,
   IntValue INT null,
   DecimalValue DECIMAL(12, 6) null,
   PropertyName INT not null,
   primary key (EntityId, PropertyName)
)

alter table Properties 
    add constraint FK63646D8550C14DC4 
    foreign key (EntityId) 
    references Entities

Which is pretty much what I need, with an exception of the column order (minor issue) and PropertyName being nvarchar(255) instead of varchar(50) (something I actually care about).

Answer 2

Besides your clustered index which you would need to manually create, yes. Do you absolutely require FNH to generate your schema?

Why don't you just generate the schema yourself specific to your requirements and then map it accordingly.

(not tested or anything, written off the top of my head)

public class EntityMap : ClassMap<Entity>
{
    public EntityMap()
    {
        Table("Entities");

        Id(x => x.Id).GeneratedBy.GuidComb();
        Map(x => x.Name).CustomSqlType("NVARCHAR").Length(50).Not.Nullable();
        HasMany<Property>(x => x.Properties)
            .Table("Properties")
            .KeyColumn("PropertyName")
            .Inverse()
            .AsBag();
    }
}

public class PropertyMap : ClassMap<Property>
{
    public PropertyMap()
    {
        Table("Properties");

        Id(x => x.Id).GeneratedBy.GuidComb();
        Map(x => x.PropertyName).Length(50).Not.Nullable();
        Map(x => x.IntValue);
        Map(x => x.DecimalValue);
    }
}