Entity Framework Code First Using One column as Primary Key and another as Auto Increment Column

Question

I have a class named Sale

public class Sale
{
    public int Id { get; set; }
    public string TrNo { get; set; }
    public DateTime Date { get; set; }
    public int CustomerID { get; set; }

    public ObservableCollection<SaleDetail> SaleDetails { get; set; }
}

And in the database, I want the Id as the Auto Increment column and the TrNo as the Primary Key column.

Please tell me how to do this using EF5 code first.

Thanks.

Something like this: http://stackoverflow.com/questions/12012736/entity-framework-code-first-using-guid-as-identity-with-another-identity-column — Jordy Langen, Jan 30 '13 at 20:22
Why do you need Id column, if TrackingNumber is a good, natural identifier? — krzychu, Aug 19 '14 at 07:06
@Seevali do you resolved this ? i has the same issue please provide solution — Neo, Nov 08 '15 at 04:29

score 48 · Answer 1 · answered Jan 30 '13 at 20:24

48

You can also do this with Data Annotations:

public class Sale
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }

    [Key]
    public string TrNo { get; set; }

    public DateTime Date { get; set; }
    public int CustomerID { get; set; }

    public ObservableCollection<SaleDetail> SaleDetails { get; set; }
}

answered Jan 30 '13 at 20:24

Corey Adler

15,897
18
66
80

2

Thanks. But not working. It created me a table that only the `Id` column as the `PK` and `AutoIncrement` column – Seevali H Rathnayake Jan 31 '13 at 09:26
No chance. Same as before. – Seevali H Rathnayake Jan 31 '13 at 19:11

score 17 · Answer 2 · answered Jan 30 '13 at 20:21

17

I believe you can do this using Fluent API

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<Sale>().Property(a => a.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
    modelBuilder.Entity<Sale>().Property(a => a.TrNo).HasKey(b => b.TrNo);
}

answered Jan 30 '13 at 20:21

Jake

733
8
23

1

Thanks. But not working. It created me a table that only the `Id` column as the `PK` and `AutoIncrement` column – Seevali H Rathnayake Jan 31 '13 at 09:27

score 7 · Accepted Answer · edited May 23 '17 at 10:31

Apparently the answer of @IronMan84 correct. But it didn't work for me. I slightly modified it to apply my another condition. And it worked. I did nothing else.

This is my solution.

public class Sale
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int Id { get; set; }

    [Key, Column(TypeName = "varchar"), MaxLength(50)]
    public string TrNo { get; set; }

    public DateTime Date { get; set; }
    public int CustomerID { get; set; }

    public ObservableCollection<SaleDetail> SaleDetails { get; set; }
}

Unfortunately I can't make the answer of @IronMan84 as the correct one as it didn't work for me.

score 4 · Answer 4 · answered Sep 22 '17 at 16:09

This helped me. Hope this helps anyone else that still looking around

public class Sale
    {
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]//switch on autogenerated
        public int Id { get; set; }

        [Key]//set as Primary key
        [DatabaseGenerated(DatabaseGeneratedOption.None)]// switch off autogenerated PK
        public string TrNo { get; set; }

        public DateTime Date { get; set; }
        public int CustomerID { get; set; }

        public ObservableCollection<SaleDetail> SaleDetails { get; set; }
}

Entity Framework Code First Using One column as Primary Key and another as Auto Increment Column

4 Answers4

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