Are data annotation allow to define compost key per model ?

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Problem

i work on asp.net core 2.1 visual studio 2017 code first with repository pattern

when do create database i do as following

Add-Migration InitialCreate

but i got error

Entity type 'Employee' has composite primary key defined with data annotations. To set composite primary key, use fluent API.

and Employee Model as below

Are Data Annotation allow to define compost key per model or not ?
I need to Create Employee Table with compost key EmployeeId , BranchCode

what i do ?

What I have tried:

public class Employee
    {
        [Key]
        [Column(Order = 1)]
        public int EmployeeId { get; set; }
        [Key]
        [Column(Order = 2)]
        public int BranchCode { get; set; }
        public string EmployeeName { get; set; }
        public int EmployeeAge { get; set; }
        public DateTime JoinDate { get; set; }
        public DateTime BirthDate { get; set; }
        public bool Active { get; set; }
    }

Posted 16-Jan-19 12:06pm

ahmed_sa

Updated 18-Jan-19 3:32am

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Richard Deeming · Answer 1 · 2019-01-18T03:32:00

No:

Keys (primary) - EF Core | Microsoft Docs[^]:
Composite keys can only be configured using the Fluent API - conventions will never setup a composite key and you can not use Data Annotations to configure one.

You have to use the fluent API to set up a composite key.

C#

class MyContext : DbContext
{
    public DbSet<Car> Cars { get; set; }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Employee>()
            .HasKey(e => new { e.EmployeeId, e.BranchCode });
    }
}

There is an open request to add support for creating composite keys using data annotations:
KeyAttribute support for composite primary key · Issue #11003 · aspnet/EntityFrameworkCore · GitHub[^]