I have the following class:
public class User
{
public Guid Id { get; set; }
public string Name { get; set; }
public Couple Couple { get; set; }
}
public class Couple
{
public Guid Id { get; set; }
public User Groom { get; set; }
public User Bride { get; set; }
}
Important points:
Bride
andGroom
properties are required- One-to-one relationship
- In the
User
class, it isCouple
required
DbContext in OnModelCreating
modelBuilder.Entity<User>().HasRequired(u => u.Couple).WithRequiredPrincipal();
modelBuilder.Entity<Couple>().HasRequired(u => u.Bride).WithRequiredDependent();
modelBuilder.Entity<Couple>().HasRequired(u => u.Groom).WithRequiredDependent();
But I can not be required!
All fileds are with null in the database!.
How do I get the field开发者_JAVA技巧s in the database as not null? If possible using the API Flient.
It should be this :
modelBuilder.Entity<User>().HasRequired(u => u.Couple).WithRequiredDependent();
modelBuilder.Entity<Couple>().HasRequired(u => u.Bride).WithRequiredDependent();
modelBuilder.Entity<Couple>().HasRequired(u => u.Groom).WithRequiredDependent();
How WithRequiredDependent Works : Configures the relationship to be required:required without a navigation property on the other side of the relationship. The entity type being configured will be the dependent and contain a foreign key to the principal. The entity type that the relationship targets will be the principal in the relationship.
Meaning : Let's consider your first line of code here. It creates a foreign key in the entity being configured (User) making it Dependant and making the other side of the relationship (Couple) Principal
Important : Don't you think the configuration you desire will generate a deadlock? I've not tested the code above, but this configuration seems to be a deadlock to me so i'm not sure if EF would allow you to create it. User must need a Couple, and Couple must need that same user i guess.
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