EF6 / LINQ MySQL-无法插入

Question

在MySQL服务器上使用EF6 / LINQ。 我有一个使用DataTable绑定到实体的BindingList的DataGridView。 一切正常，甚至删除记录。 但是我无法插入数据库中尚未存在的记录。

我的意思是，如果我从数据库中选择一条记录，然后将其删除，SaveChanges（），然后重新插入，它将重新插入自身！ 但是，如果我尝试插入前。 新的tcompanyaddress（），设置其属性，然后插入？ 不起作用

最终目标是模拟事务，清除数据库中与CompanyID FK相关的所有地址，然后仅从BindingList中重新插入最新编辑的地址。 同样，它可以工作...但不适用于新条目。

using (JobTrackerEntities context = new JobTrackerEntities())
{
    context.Database.Connection.ConnectionString += ";password=orbitman1;";
    // Update main profile
    tcompany companyRow = context.tcompany.Find(Company.CompanyID);
    companyRow.CompanyName = Company.CompanyName;
    // Update foreign profiles
    var addresses = from address in context.tcompanyaddress // Retreive all addresses that were removed
                    where address.CompanyID == Company.CompanyID
                    select address;
    // Clear existing addresses
    foreach (tcompanyaddress address in addresses)
    {
        Console.WriteLine("Remove " + address.LocationName);
        context.Entry(address).State = EntityState.Deleted;
    }
    addresses = from address in context.tcompanyaddress // Retreive all addresses that were removed
                where address.CompanyID == Company.CompanyID
                select address;
    Console.WriteLine("After clear: " + addresses.Count());
    // Replace with new addresses
    foreach (tcompanyaddress address in CompanyAddresses)
    {
        Console.WriteLine("Add " + address.LocationName);
        context.tcompanyaddress.Add(address);
    }
    // Commit transaction
    context.SaveChanges();
    addresses = from address in context.tcompanyaddress // Retreive all addresses that were removed
                where address.CompanyID == Company.CompanyID
                select address;
    Console.WriteLine("After add: " + addresses.Count());

    RefreshProfileForm();
}

Answer 1

解决方案很简单。 原来，当我向BindingList添加新地址时，我没有设置CompanyID FK，这意味着查询从不选择它。