EF creates a relational id column in the database, which is not part of the model

Question

I have this model:

public class Project
{
    public int Id { get; set; }
    public int? ParentId { get; set; }
    // some more properties...

    public List ChildProjects { get; set; }
}

In the database, the column "ProjectId" is created, which is used to keep track of the relationship to the parent project.

Since "ProjectId" is not part of the entity model, I can't reference it in my queries.

How can I prevent this column from being created, and use "ParentId" instead?

UPDATE

This is my DbContext:

public class ProjectsDbContext : DbContext
{
    public ProjectsDbContext(DbContextOptions options) : base(options) { }

    public DbSet Projects { get; set; }
}

user_5202563 · Answer

ProjectId is the EF Core conventional FK property name - {Entity Name}{Entity PK Property Name}.

As usual when conventions don't match your model, you have to use explicit configuration with either data annotations or fluent API, for instance in your case

modelBuilder.Entity()
    .HasManye(e => e.ChildProjects)
    .WithOne()
    .HasForeignKey(e => e.ParentId); // <--

For more info, see the Relationships section of the EF Core documentation.

EF creates a relational id column in the database, which is not part of the model

1 Answers