Entity-framework – Entity Framework DELETE statement conflicted with the REFERENCE constraint

I’m pretty new to EF and I have a little problem.

I just want to delete an item in my database. I’m using SQL Server 2012 Express, VS2012, AdventureWorks 2012.

The query that I execute is the following:

context = new AWEntities();
            var removedItem = context.Addresses
                .Include("StateProvince")
                .Include("SalesOrderHeaders")
                .Include("BusinessEntityAddresses").Single(d => d.AddressID == 11);
            context.Addresses.Remove(removedItem);

context.SaveChanges();

The error that I get is

The DELETE statement conflicted with the REFERENCE constraint "FK_SalesOrderHeader_Address_ShipToAddressID". The conflict occurred in database "AdventureWorks2012", table "Sales.SalesOrderHeader", column 'ShipToAddressID'.
The statement has been terminated.

Is this actually a good way to delete items and the according entries in the other tables?

Please point me into the right direction.

   public partial class Address
    {
        public Address()
        {
            this.BusinessEntityAddresses = new HashSet<BusinessEntityAddress>();
            this.SalesOrderHeaders = new HashSet<SalesOrderHeader>();
        }

        public int AddressID { get; set; }
        public string AddressLine1 { get; set; }
        public string AddressLine2 { get; set; }
        public string City { get; set; }
        public int StateProvinceID { get; set; }
        public string PostalCode { get; set; }
        public System.Data.Spatial.DbGeography SpatialLocation { get; set; }
        public System.Guid rowguid { get; set; }
        public System.DateTime ModifiedDate { get; set; }

        public virtual StateProvince StateProvince { get; set; }
        public virtual ICollection<BusinessEntityAddress> BusinessEntityAddresses { get; set; }
        public virtual ICollection<SalesOrderHeader> SalesOrderHeaders { get; set; }
    }


public partial class StateProvince
    {
        public StateProvince()
        {
            this.Addresses = new HashSet<Address>();
            this.SalesTaxRates = new HashSet<SalesTaxRate>();
        }

        public int StateProvinceID { get; set; }
        public string StateProvinceCode { get; set; }
        public string CountryRegionCode { get; set; }
        public bool IsOnlyStateProvinceFlag { get; set; }
        public string Name { get; set; }
        public int TerritoryID { get; set; }
        public System.Guid rowguid { get; set; }
        public System.DateTime ModifiedDate { get; set; }

        public virtual ICollection<Address> Addresses { get; set; }
        public virtual CountryRegion CountryRegion { get; set; }
        public virtual ICollection<SalesTaxRate> SalesTaxRates { get; set; }
        public virtual SalesTerritory SalesTerritory { get; set; }
    }
}

public partial class BusinessEntityAddress
{
    public int BusinessEntityID { get; set; }
    public int AddressID { get; set; }
    public int AddressTypeID { get; set; }
    public System.Guid rowguid { get; set; }
    public System.DateTime ModifiedDate { get; set; }

    public virtual Address Address { get; set; }
    public virtual AddressType AddressType { get; set; }
    public virtual BusinessEntity BusinessEntity { get; set; }
}


public partial class SalesOrderHeader
    {
        public SalesOrderHeader()
        {
            this.SalesOrderDetails = new HashSet<SalesOrderDetail>();
            this.SalesOrderHeaderSalesReasons = new HashSet<SalesOrderHeaderSalesReason>();
        }

        public int SalesOrderID { get; set; }
        public byte RevisionNumber { get; set; }
        public System.DateTime OrderDate { get; set; }
        public System.DateTime DueDate { get; set; }
        public Nullable<System.DateTime> ShipDate { get; set; }
        public byte Status { get; set; }
        public bool OnlineOrderFlag { get; set; }
        public string SalesOrderNumber { get; set; }
        public string PurchaseOrderNumber { get; set; }
        public string AccountNumber { get; set; }
        public int CustomerID { get; set; }
        public Nullable<int> SalesPersonID { get; set; }
        public Nullable<int> TerritoryID { get; set; }
        public int BillToAddressID { get; set; }
        public int ShipToAddressID { get; set; }
        public int ShipMethodID { get; set; }
        public Nullable<int> CreditCardID { get; set; }
        public string CreditCardApprovalCode { get; set; }
        public Nullable<int> CurrencyRateID { get; set; }
        public decimal SubTotal { get; set; }
        public decimal TaxAmt { get; set; }
        public decimal Freight { get; set; }
        public decimal TotalDue { get; set; }
        public string Comment { get; set; }
        public System.Guid rowguid { get; set; }
        public System.DateTime ModifiedDate { get; set; }

        public virtual Address Address { get; set; }
        public virtual ShipMethod ShipMethod { get; set; }
        public virtual CreditCard CreditCard { get; set; }
        public virtual CurrencyRate CurrencyRate { get; set; }
        public virtual Customer Customer { get; set; }
        public virtual ICollection<SalesOrderDetail> SalesOrderDetails { get; set; }
        public virtual SalesPerson SalesPerson { get; set; }
        public virtual SalesTerritory SalesTerritory { get; set; }
        public virtual ICollection<SalesOrderHeaderSalesReason> SalesOrderHeaderSalesReasons { get; set; }
    }