Validate data using DataAnnotations with WPF & Entity Framework?
Hello is thee any way to validate using Data Using DataAnnotations in WPF & Entity Framework? ...
entity-framework
Entity Framework CreatedBy fields not updating
Using Entity Framework I have the fields: o CreatedOn (datetime) o CreatedBy (nvarchar(50)) o ModifiedOn (datetime) o ModifiedBy (nvarchar(50)) When I add data to my table it is not adding/updating data to these columns. Am I missing something? This is a similar question to subsonic CreatedBy fields not updating ...
Delete a relationship?
What is the opposite of: Dim ad As New Address Person.AddressReference.Attach(ad) I mean how do I delete the Person.Address? (both with deleting and without - meaning only delete the relation)? ...
Undelete an entity marked as EntityState.Delete?
Hello, instead of talking let me talk with code: Dim Contact = Context.Contacts.Include("Phones") Dim phone = Contact.Phones(0) Contact.Remove(phone) How do I refresh the context now, canceling last relation deletion? I tried: Context.Refresh(RefreshMode.StoreWins, phone) 'Doesn't recover the relation Context.Refresh(RefreshMode.Sto...
Entity Framework: How to partially populate an Entity
When creating a query with EF, Normally we will create an anonymous type in order to limit the number of columns returned. But anonymous type cannot be returned or used as a parameter to a method call, which means all work related to that anonymous object should be done inside a single method. This is really bad. And certainly, we don'...
Entity Framework - track changes in associations (foreign key)
Hi, Does anyone know how to track changes in Foreign Key values mapped by EF as associations? The ObjectStateEntry.CurrentValues/OriginalValues handle only scalar types! And the AssociationChanged event does not provide any info about the reference/collection being changed. Thanks Luc ...
Entity Framework - Loading Entities from data store
Hi, Is there any event triggered after loading the entities with values from the underlying store? Thanks, Luc ...
How can i write Linq2Entities Query with inner joins
How can I get data from these related entities. I want to get these columns only: Term.Name , related Concept_Term.Weight, related Concept.Id I wrote the SQL but I don't want to use select t.Name,ct.ConceptId,ct.Weight from Term t inner join Concept_Term ct on t.Id=ct.TermId inner join Concept c on c.Id=ct.ConceptId where...
Entity Framework One-To-One Mapping Issues
Using VS 2010 beta 2, ASP.NET MVC. I tried to create an Entity framework file and got the data from my database. There were some issues with the relationships, so I started to tweak things around, but I kept getting the following error for simple one-to-one relationships Error 1 Error 113: Multiplicity is not valid in Role 'UserProf...
What Are Your Thoughts On Entity Framework 4.0?
The initial release of the Entity Framework wasn't regarded well in the development community. Developers felt a number of things were left out, and many continued to use other ORM's, such as LINQ To SQL and NHibernate. The good news, however, is that Microsoft has been hard at work on the 4.0 release of Entity Framework, which will brin...
How do I Relate these 4 Tables
Trying to setup a simple Thread/Poll table mapping. Here is what I have: Threads table ThreadID (Primary Key/Identity Column) Polls table PollID (Primary Key, FK for ThreadID for one-to-one relation) Question PollOptions table PollOptionID (Identity/Primary Key) Text PollID PollVotes table PollVoteID (Primary Key/Identity...
Entity Framework EDM.Binary Mapping to VB type
Hi, I'm using POCOs with the latest version of EF 4.0 and have a timestamp field on my SQL Server 2008 db for handling optimistic concurrency. The designer has created a mapping for the field with as an entity type of Binary. How should this be represented in my VB POCO as EDM.Binary is not available there? When I have the field as a B...
Problem with EDM in ASP.NET MVC
Hi there, I don’t know I am really stuck with this problem and I can’t able to get the solution. I have this code to update my contact and contact group. var originalContact = GetContact(contactToEdit.Id); // Update with new group originalContact.groups = GetGroup(groupId);// Exception : A referential integrity con...
Entity Framework duplicating every insert
I'm trying to perform an import from Excel into an EF container, but every time I attempt this, every new record gets inserted twice. The 'AddToEntitySet' call only ever happens once, as does the SaveChanges, but immediately afterward, there are two of each record. What am I doing wrong? int rowNum = 1; foreach...
How do I change a foreign key association using Entity Framework?
Using ASP.NET Entity Framework, how can I change the Foreign Key association between two entities? Here's an example scenario: --------------- ---------------- | Customer | | Class | --------------- ---------------- | ID | | Desctription | | Name | | Name | | ClassID (FK)|-----| ID ...
Is an outer join possible with Linq to Entity Framework
There are many examples of outer join using Linq to Sql, all of them hinging on DefaultIfEmpty() which is not supported with Linq to Entity Framework. Does this mean that outer join is not possible with Linq to Entity using .NET 3.5 (I understand that DefaultIfEmpty is coming with 4.0 --- but that's not an option at this time for me) C...
Entity Framework - Insert Related Entities
I'm trying to insert an entity (document) with the EF and ASP.NET. My entity model and schema is below, and I'm getting an unusual error about a foreign key mismatch on the Tutors table. Entities in 'SchoolEntities.Courses' participate in the 'FK_Courses_Tutors' relationship. 0 related 'Tutors' were found. 1 'Tutors' is expected. I'm...
Entity Framework automatically attach entities
I'm using the Entity Framework, and it's entities are used are Database representation AND business object. So it means that some entities that are manipulated should always stay detached from the context. I managed to read and write data from the database but I have a small problem when updating: I have a table "Stock" which is linke...
Entity Framework map multiple tables to one entity
I have a database with a table for active orders and one for inactive orders. I would like to model this in Entity Framework as one entity called Orders. I also need a way to determine if an order in this collection is active or not, preferably by having a status property on the entity that is set according to what table it is in. Is th...
Entity Framework Endpoint Multiplicity
Say I have 3 tables in a Tennis Application (stripped down removing irrelevant info): Competitions Id (PK) Matches Id (PK) CompId (FK) CourtAssignments CompId (PK),(FK) CourtNumber (PK) MatchId (FK), (Unique) To describe the above: A match consists of 2 people playing tennis against eachother on a court. A competition consists ...