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Unit Test with transaction: CREATE DATABASE statement not allowed within multi-statement transaction
I believe you are taking the pattern of rolling back database side-effecting Integration / Unit Tests done under an uncommitted transaction (such as TransactionScope) a bit far :) Code First EF is attempting to create the database under the context of the ambient TransactionScope, which isn't possible. In Sql Server (and possibly other RDBMS's), it isn't possible to execute certain statements, s

Categories : Entity Framework

Entity Framework SDF database size issue
Change connection string: <add name="Entities" connectionString="metadata=res://*/DBModel.csdl|res://*/DBModel.ssdl|res://*/DBModel.msl;provider=System.Data.SqlServerCe.4.0;provider connection string=&quot;data source=|DataDirectory|DB.sdf;Max database size=4091&quot;" providerName="System.Data.EntityClient" /> Also note that the max size for a SQL Compact database is 4 GB

Categories : Entity Framework

Total participation in Dia
You can add new shapes to the software, but you to create them first.. I've just done an example for you (it's in Spanish but I think you'll understand): Create the new shape in dia Export to a shape format Select File → Sheets and Objects from the menu to open the Sheets and Objects dialog or press F9. Sheets and Objects dialog. Click on the New button - a new dialog will be op

Categories : Entity Framework

How to add new tables in to an exisitng Entity framework
If you click Update model from database you get a window with a TabControl in it. The tab items are Add, Refresh and Delete. From the Add tab check from the treeview the tables that you want to add. Then those selected tables are inserted into the edmx file

Categories : Entity Framework

Entity framework tracking wrong model object after helper method
The line... AgentTransmission sub = master; ...doesn't copy master to sub, but assigns it to sub, because AgentTransmission is a reference type. So everything you do to sub you do to master. You either must clone master to sub (create a new object and copy its properties), or re-fetch the master object from the database after the CreateSubStat call.

Categories : Entity Framework

Add a record via Entity Framwork containing no values
Entity framework will generate a sql from these values, so to achive what you need, do one of those two options Don't map the hash property and let the sql database inserts the default which is a newid(), but this means EF will never know about that column and you cannot retrieve it as you do normally when you load your entity. Add a constructor to your entity and initialize the hash propert

Categories : Entity Framework

Is there an absolute model answer for Entity-Relationship diagram?
A Conceptual Model is used to represent a domain of discourse to aid you and the users understand that domain. As such the wording and form of that representation should be that most aids you and the users in that understanding. Therefore, should you choose to include an Entity Relationship Diagram as part of the Conceptual Model, the terms, notation and diagrammatic conventions used should be th

Categories : Entity Framework

EF code first with Repository and unit of work
The problem you're describing here took me a real long to get my head around a few years ago. You're definitely on the right track wanting to separate data access and business logic, and the business logic should be in its own project, so what you need to do is create an abstraction in the form of an repository interface. Something like: interface IPostRepository { void Insert(Post post);

Categories : Entity Framework

Entity Framework 6.0: how to use edmx context when connection is configured in code?
Found it. Ok so in EF 6.0 the DbContext no longer has a constructor that accepts a connection, but there is one that accepts a connection string. Just modify the generated code and add the following constructor: public Entities(String connectString) : base(connectString) { } Then directly pass the connection string and it will work.

Categories : Entity Framework

EF is creating 2 foreign keys for navigation property
Ok I'm able to get past this but the bounty is still available for a better way. Gert's comments in this answer helped me put it together. Basically since there are 2 User entities on the Earning, EF is not going to assume which of them is bi-directional for the Earnings collection on the User. Using [InversePropoperty] attribute works but I'm not able to configure this using Fluent Api: Solut

Categories : Entity Framework

Entity Framework 6 TPT, Multiple collections of same type on parent entity
am not sure if what you are seeking is possible. you want EF To Deferenciate between two collections of the same type,both optional,one with cascading on delete and the other no. EntityFramework map Fluid to One Table and only one table,this table has some foreign keys columns to represent the relationship with the the Tool.according to your example you will end up having two foreign keys in the s

Categories : Entity Framework

Configuring 1 to (1 or zero) relationship using EntityTypeConfiguration
You could do it using Data Annotations instead: For your Garden class: [Required, ForeignKey("House")] public int HouseID { get; set; } public virtual House House { get; set; } For your House class: [ForeignKey("Garden")] public int? GardenID { get; set; } public virtual Garden Garden { get; set; }

Categories : Entity Framework

Where does Inversion of Control exist in Entity Framework?
Inversion of Control is a pattern that aims at loosely coupling an application. It puts the application in charge of all of its dependencies (whether or not they are in libraries or frameworks). EF is not an application, it is a library. You can wire it up with IoC, but since it is not an application, it contains no IoC. That said, it is possible to develop frameworks and libraries to be IoC or

Categories : Entity Framework

Entity Framework Many TO Many Relationship with Primary Key
You need to model your classes similar to your DB, why don't you simply add the association tables? I mocked up your DB and there is no problem as long as you model all the tables. Test it for yourself, create an EF project .edmx using code first from existing DB, I think the answer will be obvious.

Categories : Entity Framework

Entity Framework Code First: how to map multiple self-referencing many-to-many relationships
By adding this in the DbContext.OnModelCreating method: UPDATE Added table-naming map according to nameEqualsPNamePrubeGoldberg's comment above: modelBuilder.Entity<Person>().HasMany(x => x.Brothers).WithMany() .Map(x => x.ToTable("Person_Brothers")); modelBuilder.Entity<Person>().HasMany(x => x.Sisters).WithMany() .Map(x => x.ToTable("Person_Sisters")); I got t

Categories : Entity Framework

How do I get my DataBase First EF 6.1 Entities to become a change tracking proxies
So, the answer lies in using the correct Namespace for IEntityWithChangeTracker. In EF6.x if you test with System.Data.Entity.Core.Objects.DataClasses.IEntityWithChangeTracker your entity will return true. Thanks Fred Bao of MSFT

Categories : Entity Framework

Entity Framework 6.1.1 When using same foreign key property in two child classes giving “property name is already defined” error
I have noticed that this happens when you establish a navigation property, and then add a scale property, both properties (scalar and navigation) associated with a single foreign key. Perhaps your case.

Categories : Entity Framework

Proper way to generate a view from a many to many relationship?
At present the scaffolding templates don’t support generating views that require the selection and association with more than one entity – the “many” end of the association. Make sure to check out this blog article http://blogs.msdn.com/b/mcsuksoldev/archive/2013/09/20/managing-entity-relationships-with-mvc-scaffolding.aspx

Categories : Entity Framework

EF6 + Migrations + SqlServer/SqlCe4
The section: <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework"> <parameters> <parameter value="v11.0" /> <parameter value="System.Data.SqlClient" /> <parameter value="System.Data.SqlServerCe.4.0" /> </parameters> </defaultConnectionFactory> Is completely broken, and several seci

Categories : Entity Framework

auto update code first from database model, is it possible?
Yes it is, if you use Reverse Engineer Code First to do so. It will create POCOs exactly like Code-First, but it will do so based completely on the current database. No .edmx file and no T4 template. Just Code-First. You should know, by the way, that this (along with regular Code-First) are going to be the only ones allowed in EF7. They are getting rid of many things to try to slim it down, and b

Categories : Entity Framework

Entity Framework Database Generation Power Pack?
You should have a look at Database.SetInitializer, which mainly determines what happens if there is no database present when the application is started for the first time, and migrations which can be used to update the datebase when a new application version (which requires an updated database) has been deployed. If the built-in support for migrations data aren't enough, you also have the ability

Categories : Entity Framework

How can you change the parameterless constructor of an Entity Framework 6 database-first generated class?
You can't implement a 2nd parameterless constructor User(), because there is already one in the auto-generated class. Hence, you have only 2 options to resolve this issue: Inherit from the original class User (see below). Modify the T4-template so the parameterless constructor is generated with the extra code DateCreated = DateTime.Now; you want to add. That will generate the extra code each ti

Categories : Entity Framework

Prevent EF6 from generate navigation properties
You must edit the t4 template that builds the model classes to get this done. In your project you'll find two .tt files, something like ModelName.Context.tt and ModelName.tt. The latter is the one that builds the model classes. Look for these two lines this.<#=code.Escape(navigationProperty)#> = new HashSet<<#=typeMapper.GetTypeName(navigationProperty.ToEndMember.GetEntityType())#&g

Categories : Entity Framework

EntityFramework: unable to determine the provider name for provider factory of type 'system.data.sqlclient.sqlclientfactory'
I have finally discovered that the error was caused by this configuration section (that now I don't use anymore): <system.data> <DbProviderFactories> <add name="MySQL Data Provider" invariant="MySql.Data.MySqlClient" description=".Net Framework Data Provider for MySQL" type="MySql.Data.MySqlClient.MySqlClientFactory, mysql.data" /> </DbProviderFactories>

Categories : Entity Framework

Entity Framework many to many relationship Delete
Curious why you don't model those other tables like UserRoles, are you just lazy? =) But seriously, what you're doing is fine however for mass deletes EF doesn't have a bulk delete capability, you are better off simply executing the DELETE statement directly, like this: using (System.Data.Common.DbCommand cmd = Context.Database.Connection.CreateCommand()) { cmd.CommandText = @"DELETE FROM Tab

Categories : Entity Framework

Entity Framework 6 Code First: specific model design implementation
A couple of observations: Design 1 seems appropriate, unless one JobReport should be able to reference multiple projects belonging to different customers. The ProjectID property doesn't belong in the Customer type, right? The Projects collection is rightfully there, though. The Project type should have a JobReports collection that lists all reports belonging to a specific object. This is a pro

Categories : Entity Framework

IdentityDbContext, DbContext and Relationships‏
A better idea would be to use the IdentityDbContext only, instead of using your other context. That said, try to move everything into the identity context. This will work, because the identity context inherits the normal context.

Categories : Entity Framework

EF 6 Code-First TPH Inheritance Results in Migrations with Duplicate Columns (sometimes in triplicate)
OK, the problem was that we were using ViewModels with MVC and the Scaffolder made the ViewModels inherit from the abstract, base-class Model of ContactInfo instead of the ContactInfoViewModel. We heavily modified the basic scaffolder to do this, so this was really our code that had a bug, not Microsoft's. Since ViewModels are supposed to be ignorant of the database, we didn't have any mapping e

Categories : Entity Framework

Entity Framework Cascading Delete
You need to make ActorID in your UseCase class as a nullable int. EF is throwing that error because it sees 2 foreign keys that are required in a single class. Having that would create multiple cascade paths--something that SQL Server is, unfortunately, ill-equipped to handle. In any case, making Actor optional on your UseCase class will mean that the Actor won't be deleted when the UseCase is, w

Categories : Entity Framework

Benefits of EF Code First?
The capabilities of code first are the same since you have the same ability to express all the features of EF manually in your code. The main difference is that you don't use a designer to generate your EF code. This offers some benefits since you can decouple your entity classes from the EF context. The main benefit of this is that you can use plain old c# classes that aren't necessarily tied to

Categories : Entity Framework

Storing IEnumerable in Entity Framework
You cannot save multiple records in single column of the relational database. There is no such data type that supports this. You can create a separate table for Image Uris and then store your image Uris there. Your entity code would look something like this: public class Product { [Key] public int Id { get; set; } public string Title { get; set; } public string Description { g

Categories : Entity Framework

Return collection with flag for if items have children
I would perhaps do something like this. public class CustomerDto { public string Name { get; set; } public int AddressCount { get; set; } } var result = from w in context.Customers select new { Name = w.Name, AddressCount = w.Addresses.Count }; var ret = new List<CustomerDto>(); foreach (var customer in result) { var newCustomerDto = new Custo

Categories : Entity Framework

Update Entity in ef
You need to change the object state before you call SaveChanges: public void UpdateResult(Result result) { // The missing something: _context.Entry(result).State = EntityState.Modified; _context.SaveChanges(); } Another way would be to call: _context.Attach(result); Just before you start modifying your object. In this case you'd only need to call Save Changes afterwards and your'

Categories : Entity Framework

EF 6 Code First migrations warn of or prevent destructive updates
This has been raised as an issue already but rejected as "by design". Decided this is by design - we only warn for automatic migrations with data loss. See the bug here.

Categories : Entity Framework

Many to Many Relationship EF Code First
Unfortunately, if you use a intermediary table with additional properties (or really, just if you define a specific class to manage that relationship instead of letting EF handle it automatically), you lose the ability to have a direct navigation property. You'll have to change your models to: public class Course { ... public List<StudentCourses> Students { get; set; } } And pu

Categories : Entity Framework

Entity Framework Migrations "context has changed" error persists even after reset all migrations
If you care nothing for your existing data, the following is sure to work: Throw away your database Throw away all the migration files Run add-migration Run update-database It's a bit of a steamroller, but it will get you out of trouble if you're not interested in finding out what the trouble actually is.

Categories : Entity Framework

Entity Framework gargantuan SQL from simple LINQ
I'm wondering what all the NULL as varchar/varbinary and why is this generated for every single type of File when they are in the same table? It looks like you are using Code First approach with the default Table-Per-Hierarchy (TPH) mapping strategy in your solution. In case of TPH, one big table is created for a hierarchy of classes (in your case, File & descendants). All non-primary

Categories : Entity Framework

Create Tree with entity framework
You're not correctly implementing the ForeignKey annotation. You would need to do something like this instead: [Key] public int Id { get; set; } public string Name { get; set; } public int ParentID { get; set; } [ForeignKey("ParentID")] public Node Parent { get; set; } This code above will then allow you to have separate Nodes that will then be able to have a Parent node assigned to them. Eac

Categories : Entity Framework

Symfony 2 Entities relationship inter bundle
Look at this line: @ORMOneToOne(targetEntity="MyCompanyDataBundleEntityCustomer") try without first "", because it isn't in "MyCompanyAppBundleEntity" namespacefolder: @ORMOneToOne(targetEntity="MyCompanyDataBundleEntityCustomer") If path is relative it is assumed to be relative to the bundle root. Edited: After comment disuss: (i mean this)... in my proj im using YAML, so my descriptions

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