Entity Framework Core: Cannot insert explicit value for identity column in table

Question

I'm using Entity Framework Core, and cannot insert an explicit value for the identity column in table

DBContext:

  modelBuilder.Entity<TbUser>(entity =>
            {
                entity.Property(e => e.Jid)
                    .HasColumnName("JID")
                    .ValueGeneratedOnAdd();
}

TBUser:

        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Jid { get; set; }

Answer 1

In your EF model code, you're defining the column Jid as [DatabaseGenerated(DatabaseGeneratedOption.Identity)]

This tells entity framework that the database will generate a value for this field . Logically then, you should not set the value in code.

If you want to manually set the values in this field you need to remove the DatabaseGenerated decorator above.

Answer 2

Make sure the IDENTITY_INSERT is off. That way the identities for every insert will need to be provided explicitly.

SET IDENTITY_INSERT [ [ database_name . ] schema_name . ] table_name { ON | OFF } 

More details on Identity_insert