ASP.net Core 7 same model multiple times

Question

I have a data model where I am connecting to the same table 3 times. I can do this in SQL by using aliases, but I am unsure if it is possible to do this in ASP.NET Core 7 MVC with Entity Framework. Are you able to "alias" a model and have the same model in a view 3 times?

Answer 1

You could try as below:

Create two Entity

 public class EntityA
    {
        public int Id { get; set; }
        public string? PropA { get; set; }
        public int ETB1Id { get; set; }
        public EntityB ETB1 { get; set; } = default!;
        public int ETB2Id { get; set; }
        public EntityB ETB2 { get; set; } = default!;
        public int ETB3Id { get; set; }
        public EntityB ETB3 { get; set; } = default!;    

    }

    public class EntityB
    {
        public int Id { get; set; }

        public string? PropB { get; set; }   
        
    }

DbContext:

public class AppDbContext : DbContext
{
    public AppDbContext(DbContextOptions<AppDbContext> options)
        : base(options)
    {
    }

    public DbSet EntityA> EntityA { get; set; } = default!;
    public DbSet< EntityB> EntityB { get; set; } = default!;
    

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        // I tried with one to one relationship,it also works for one to many relationship
        modelBuilder.Entity<EntityA>().HasOne(x => x.ETB1).WithOne().OnDelete(DeleteBehavior.Restrict);
        modelBuilder.Entity<EntityA>().HasOne(x => x.ETB2).WithOne().OnDelete(DeleteBehavior.Restrict);
        modelBuilder.Entity<EntityA>().HasOne(x => x.ETB3).WithOne().OnDelete(DeleteBehavior.Restrict);
    }
}

load related data in controller:

 var targetitems = _context.EntityA.Include(x => x.ETB1).Include(x => x.ETB2).Include(x => x.ETB3).ToList();

Succeeded: