Insert via Entityframework error "IDENTITY_INSERT is set to OFF"

Question

I have several models and for some reason one of them presents the following error:

Cannot insert explicit value for identity column in table 'tbl_boleto' when IDENTITY_INSERT is set to OFF.

I remember I once entered a record, but now I can’t enter it anymore.

    var NewBoleto = new Boleto
    {
        ClienteId = 3,
        DataVencimento = DateTime.Today,
        Valor = 4,
        DataBaixa=null,
        DataEmissao = DateTime.Now,
        DataReferencia= DateTime.Today,
        DataPagamento = null
    };

   db.Boletos.Add(NewBoleto);
   db.SaveChanges();

A model:

using System;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace WMB.Models
{
    [Table("tbl_boleto")]
    public class Boleto
    {
        [Key]
        [Column("int_ID")]
        public int BoletoId { get; set; }

        [Column("int_IDC")]
        public int ClienteId { get; set; }

        [Column("sdt_Dataemissao")]
        public DateTime DataEmissao { get; set; }

        [Column("sdt_DataVencimento")]
        [DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:yyyy-MM-dd}")]
        [Required(ErrorMessage = "Data de Vencimento é requerida")]
        [Display(Name = "Data de Vencimento")]
        [DataType(DataType.Date)]
        public DateTime DataVencimento { get; set; }


        [Column("sdt_dataPagamento")]
        public DateTime? DataPagamento { get; set; }


        [Column("sdt_dataBaixa")]
        public DateTime? DataBaixa { get; set; }

        [Column("sdt_DataReferencia")]
        [DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:yyyy-MM-dd}")]
        [Display(Name = "Referência 01/mm/aaaa")]
        [DataType(DataType.Date)]
        public DateTime DataReferencia { get; set; }

        [Column("cur_valor")]
        public decimal? Valor { get; set; }

        [Column("cur_valorPago")]
        public decimal? ValorPago { get; set; }

        [Column("int_status")]
        public byte Status { get; set; }

        [Column("int_TotalMeses")]
        public byte? TotalMeses { get; set; }

        [Column("int_Tipo")]
        public byte Tipo { get; set; }

        [Column("int_ViewClient")]
        public byte? QtdVisualizacoes { get; set; }


        public virtual Cliente Cliente { get; set; }

        //[ForeignKey("BoletoId")]
        //public virtual BoletoTXT boletoTxt { get; set; }

    }
}

When looking through the SQL profile for some unknown reason for this model it is sending the PK field which is autonumeric. (int_ID) For all other models is working.

Updating: I found the reason for the mistake, but I don’t know why. I have another Model called Boletotxt that has a connection with Boleto N-1

 [Table("tbl_boleto_TXT")]
    public class BoletoTXT
    {
        [Key]
        [Column("int_ID")]
        public int BoletoTXTId { get; set; }

        [Column("int_IDBoleto")]
        public int BoletoId { get; set; }

        [Column("str_Mensagem")]
        public string Menssagem { get; set; }

        [ForeignKey("BoletoId")]
        public virtual ICollection<boleto> boleto { get; set; }

    }

The problem is this line

[ForeignKey("BoletoId")]
public virtual ICollection<boleto> boleto { get; set; }

But I’ve used it in other projects and I don’t remember making a mistake. I’m making the wrong relationship?

Answer 1

the problem was how to create relationships between boletos and boletoTXT

as had been made boletoTXT had several boletos, so he made use of the foreign key.

In the model Boletos got

public virtual ICollection<BoletoTXT> BoletoTXT { get; set; }

and the Boletostxt model

public virtual boleto Boleto { get; set; }

and it’ll all work out