How to map child entity to parent entity without introducing primitive type parent linker in child entity?
I have these classes:
public class Product
{
[Key]
public virtual int ProductId { get; set; }
public virtual string ProductName { get; set; }
public virtual string Category { get; set; }
public virtual IList<ProductPricing> ProductPriceList { get; set; }
1679644129
public virtual byte[] Version { get; set; }
}
public class ProductPricing
{
// no ProductId here
public virtual Product Product { get; set; }
[Key]
public virtual int ProductPricingId { get; set; }
public virtual 开发者_运维知识库DateTime EffectiveDate { get; set; }
public virtual decimal Price { get; set; }
}
This is my modelBuilder:
modelBuilder.Entity<Product>().
HasMany(x => x.ProductPriceList)
.WithRequired()
.HasForeignKey(x => x.Product);
This is the error:
The foreign key component 'Product' is not a declared property on type 'ProductPricing'. Verify that it has not been explicitly excluded from the model and that it is a valid primitive property.
UPDATE
I've tried the following, corresponding errors below the code
modelBuilder.Entity<Product>()
.HasMany(x => x.ProductPriceList)
.WithRequired();
{"Invalid column name 'Product_ProductId1'.\r\nInvalid column name 'Product_ProductId'.\r\nInvalid column name 'Product_ProductId1'."}
modelBuilder.Entity<Product>()
.HasMany(x => x.ProductPriceList)
.WithRequired()
.Map(x => x.MapKey("ProductId"));
{"Invalid column name 'Product_ProductId'."}
modelBuilder.Entity<Product>()
.HasMany(x => x.ProductPriceList)
.WithRequired(x => x.Product);
{"Invalid column name 'Product_ProductId'.\r\nInvalid column name 'Product_ProductId'."}
modelBuilder.Entity<Product>()
.HasMany(x => x.ProductPriceList)
.WithRequired(x => x.Product)
.Map(x => x.MapKey("ProductId"));
{"Multiplicity constraint violated. The role 'Product_ProductPriceList_Source' of the relationship 'TestEfCrud.Mappers.Product_ProductPriceList' has multiplicity 1 or 0..1."}
If it could help, here's the DDL:
create table Product
(
ProductId int not null identity(1,1) primary key,
ProductName varchar(100) not null,
Category varchar(100) not null,
Version rowversion not null
);
create table ProductPricing
(
ProductId int not null references Product(ProductId),
ProductPricingId int identity(1,1) not null primary key,
EffectiveDate datetime not null,
Price decimal(18,6) not null
);
UPDATE 2
I've tried this answer, which looks a bit similar to my case, mapping originated from child entity How to map parent column in EF 4.1 code first
However, using this:
modelBuilder.Entity<ProductPricing>()
.HasOptional(x => x.Product)
.WithMany()
.Map(x => x.MapKey("ForeignKeyColumn"));
and this:
modelBuilder.Entity<ProductPricing>()
.HasRequired(x => x.Product)
.WithMany()
.HasForeignKey(x => x.Product);
Both resulted to this error:
{"Invalid column name 'Product_ProductId1'.\r\nInvalid column name 'Product_ProductId1'.\r\nInvalid column name 'Product_ProductId1'."}
I don't understand why do you use fluent mapping? Your model should be mapped by default conventions. If you want to map it with fluent mapping use:
modelBuilder.Entity<Product>()
.HasMany(x => x.ProductPriceList) // Product has many ProductPricings
.WithRequired(y => y.Product) // ProductPricing has required Product
.Map(m => m.MapKey("ProductId")); // Map FK in database to ProductId column
This has the correct answer:
http://agilenet.wordpress.com/2011/04/18/entity-framework-code-first-specify-foreign-key-name-in-one-to-many-relationship-with-fluent-api/
I almost got it:
modelBuilder.Entity<ProductPricing>()
.HasRequired(x => x.Product)
.WithMany()
.Map(x => x.MapKey("ProductId"));
I just forgot to put the principal's dependent(i.e. ProductPriceList. I hope I'm getting the right terminology, wanted to stay away from parent child terminology ^_^):
modelBuilder.Entity<ProductPricing>()
.HasRequired(x => x.Product)
.WithMany(x => x.ProductPriceList)
.Map(x => x.MapKey("ProductId"));
Entity Framework's Fluent Mapping is hardly fluent, there's some stutter you could unwittingly commit if you are not very familiar with each method's nuances :-) Lookie that, I almost got it correct. Passing both ProductPricing
and ProductPriceList
look redundant, hardly intuitive.
EF's fluent mapping is hardly a good fluent(of which intuitiveness should be an innate quality) interface citizen, isn't it?
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