Hi there,

While working through chapter 14 I was unable to complete the steps to add to the database diagram, the two new tables 'PhotoAlbum' and 'Picture' because the module listing in the Server Explorer was missing the Database Diagrams option. Why would that be?

To try and work around this, I opened SQL Server Management Studio and accessed the database file and added the diagram to match the instructions. I was then able to complete the steps to add the two new tables to the Entity Framework model file. However, when I try to run the NewPhotoAlbum.aspx page, I get a series of errors saying "The type or namespace name 'PhotoAlbum' could not be found (are you missing a using directive or an assembly reference?)'.

I suspect that this has something to do with how I had to establish the foreign key in the PhotoAlbum table.

I opened and ran the code from Chapter 14 and I runs fine but the code is slightly different than what I had produced. The class definition in the NewPhotoAlbum.aspx.cs file was: 'public partial class _NewPhotoAlbum : System.Web.UI.Page' while the same line in my version lacked the leading underscore in front of NewPhotoAlbum (the 'Inherits' property in the my NewPhtoAlbum.aspx file referred the same form of NewPhotoAlbum). Otherwise, the code looked identical between the files I compared.

Anyone know why I wouldn't have the Database Diagram option in my Server Explorer?

Thanks,
Pete

Hi Pete,

Not sure what happened there. Did you create the database outside of Visual Studio? I have seen this before in SSMS when I create a database with Entity Framework code first (that automatically creates the database). Then when I try to add a diagram, I get a dialog about missing objects to support diagrams. After confirming, the missing objects get created and I can create a diagram. Maybe the same thing happens in VS but it doesn't have the tools to create the missing objects? Just a guess....

Imar

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Imar Spaanjaars
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Author of Beginning ASP.NET 4.5 : in C# and VB, Beginning ASP.NET Web Pages with WebMatrix
and Beginning ASP.NET 4 : in C# and VB.
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