Question

In my “web store” mvc app I want to add items to database. Items table has CreatedBy field and it is a foreign key from User table UserId field. Everything was working before I put the database into the App_Data folder. Now I get the SqlException when trying to create a new Item:

The INSERT statement conflicted with the FOREIGN KEY constraint “FK_Item_contains_User”. The conflict occurred in database “C:\USERS\ALEKSEY\REPOS\2\WEBSTORE\WEBSTORE\APP_DATA\WEBSTORE.MDF”, table “dbo.Users”, column ‘UserId’.

Here is the Create method of ItemRepository class:

public Item CreateItem(int productId, Guid userId)
    {
        var item = new Item
            {
                ProductId = productId,
                CreatedBy = userId,
            };
        _dataContext.Items.InsertOnSubmit(item);
        _dataContext.SubmitChanges(); // in this line the exception occures !
        return item;
    }

Here is the controller method Create:

    [HttpGet]
    public ViewResult Create()
    {
        var p = _productRepository.CreateProduct("", "", 0, "", "", "");
        var userId = (Guid)Membership.GetUser().ProviderUserKey;
        var item = _itemsRepository.CreateItem(p.ProductId, userId);

        // some code
        return View(model);
    }

Besides, I use Linq to Sql model drag an’ drop approach.
Here is the changed web.config connection string part:

<connectionStrings>
<add name="WebStoreConnectionString" connectionString="Data Source=(LocalDB)\v11.0;
     AttachDbFilename=|DataDirectory|\WebStore.mdf;Integrated Security=True;Connect Timeout=30" 
    providerName="System.Data.SqlClient" />

<add name="DefaultConnection" connectionString="Data Source=|DataDirectory|\aspnet.sdf" 
     providerName="System.Data.SqlServerCe.4.0" />

As I said everything was working before I moved the database to App_Data file. I also tried to remove the dependency between Items and Users tables – the exact same exception.

Any help would be appropriate. Thanks in advance!

Edits:

Ok, now I really broke the dependency between Items and Users tables and no exception occures. But! I have to somehow know who has created each product, so breaking the dependency is not an option. I also tried to remove all code that initializes the CreatedBy field.

Any ideas??

Edits (part 2):

The second comment below gives a great advise! I found that all users that are created are stored now in the aspnet.sdf database!!!
But if I remove the connection string “DeafaultConnection”:

<add name="DefaultConnection" connectionString="Data Source=|DataDirectory|\aspnet.sdf"
  providerName="System.Data.SqlServerCe.4.0" />  

I will get ConfigurationErrorsException:

"The connection name 'DefaultConnection' was not found in the applications 
configuration or the connection string is empty." 

in the folowing line:

 var userId = (Guid)Membership.GetUser().ProviderUserKey;

Answer 1

Ok, as I guessed the issue was in the configuration. Each provider (for some reason) in the connection string had “DefaultConnection”. I changed it to “WebStoreConnectionString”. And now everything works!

p.s. thanks @w0lf, he pushed the thoughts in the right direction)