Geek Answers Handbook

The problem of the cardinality of the Entity Framework structure in the association 0 ... 1

I have database tables that look like this:

Schema diagram

A Taskmay Moduleor may not be mapped (0 ... 1). First, I use the Entity Framework database, and when I generated the model from the database, the Task object came with the modules as a collection (0 or more). Therefore, I opened my EDMX and changed the navigation property "Modules" to "Task" to 0 ... 1.

Edmx

Now when I try to compile, I get this error:

Error 3003: a problem with displaying fragments starting from line 1241: Considering the power of the task of the final member of the association, it should be mapped to the key columns of the TaskModule table. Either lock the display, or change the multiplicity of this end.

, , . . , , , - , . :

TaskModule Association

Visual Studio 2010 SP1, Entity Framework 4.3.1.0, SQL Server 2008 R2.

+5
2

- TaskModule. (TaskId, ModuleName) (TaskId). , .

+5

, , :

TaskModule "--", -to-oneOrZero.

edmx many-to-many , .

, , EF!

+1

More articles:


All Articles