POCO in the Entity Framework: Part 1 - The Experience

POCO in the Entity Framework: Part 1 - The Experience | ASP NET Hosting

POCO in the Entity Framework: Part 1 - The Experience | ASP NET Hosting — Fri, 22 May 2009 04:01:22 GMT

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re: POCO in the Entity Framework: Part 1 - The Experience

hans — Fri, 22 May 2009 05:41:43 GMT

In LINQ, it has a CreateDatabase() method where I can create the database based on the POCO.

Does EntityFramework have that kind of method?

re: POCO in the Entity Framework: Part 1 - The Experience

dmitry — Fri, 22 May 2009 07:55:19 GMT

Is there a way to use "HashSet<Product> Products" instead of "List<Product> Products" in the Category POCO?

POCO в Entity Framework: первый опыт

progg.ru — Fri, 22 May 2009 08:02:08 GMT

Thank you for submitting this cool story - Trackback from progg.ru

re: POCO in the Entity Framework: Part 1 - The Experience

Matt — Fri, 22 May 2009 10:47:10 GMT

@dmitry: HashSet<T> should work as it implements ICollection<T>.

ADO.NET team blog : POCO in the Entity Framework: Part 1 - The Experience

9eFish — Fri, 22 May 2009 11:45:53 GMT

9efish.感谢你的文章 - Trackback from 9eFish

re: POCO in the Entity Framework: Part 1 - The Experience

Brendan — Fri, 22 May 2009 11:49:33 GMT

Is partial table mapping supported via the use of defaults defined within the model? e.g:

Table: Id int PK,

Col1 varchar(250) null,

Col2 bit not null

I'd create the model to match the above but miss out Col2 and provide a default of null within the SSDL. My POCO would then just have the Id and Col2 properties. Is this possible?

re: POCO in the Entity Framework: Part 1 - The Experience

Brendan — Fri, 22 May 2009 11:55:40 GMT

I meant Col1 (in my above question) for the POCO property!

re: POCO in the Entity Framework: Part 1 - The Experience

dmitry — Fri, 22 May 2009 16:01:54 GMT

@Matt, for some reason HashSet/ISet does not work as an automatic property. The exception says something like "unable to to create property x for type y." It does work if you create a backing variable and initialize it.

ICollection/IList and List all work fine with an automatic property.

re: POCO in the Entity Framework: Part 1 - The Experience

Rick — Fri, 22 May 2009 16:54:53 GMT

Great article.

Towards the end of the article though, you wrote, "In the meantime, take a look at the complete solution (attached) if you are interested in the sample code covering all the concepts we covered here."

I don't see a link to the sample code anywhere though. Can you point me to the location of the sample code download?

Also, can anybody provide any references that show how to use generated entities (EntityObject) that support changes on the entity made after the context has been detached?

Thanks,

Rick

POCO in the Entity Framework: Part 1 - The Experience - ADO.NET Team Blog

DotNetShoutout — Fri, 22 May 2009 17:22:56 GMT

Thank you for submitting this cool story - Trackback from DotNetShoutout

re: POCO in the Entity Framework: Part 1 - The Experience

Muhammad Mosa — Fri, 22 May 2009 18:05:17 GMT

Nicely done Faisal! well presented and explained.

That was really an addition to existing documentation.

re: POCO in the Entity Framework: Part 1 - The Experience

Faisal — Fri, 22 May 2009 22:28:43 GMT

Hi Rick,

I have fixed the issue with the attachment not being a part of the post. The post now has an attachment that you can download.

-faisal

Update on the Entity Framework in .NET 4 and Visual Studio 2010

ADO.NET team blog — Sat, 23 May 2009 00:17:31 GMT

Since we shipped the .NET Framework 3.5 SP1 and Visual Studio 2008, we’ve been working on the next version

re: POCO in the Entity Framework: Part 1 - The Experience

nhibernateuser — Sun, 24 May 2009 15:54:52 GMT

you are completely missing the point with the "generate from the DB"...

POCO idiom is used in DDD, there is no reason to abstract the framework away with POCO once my goal is to "design" from the DB. And no ability to create the DB from POCO. And the designer is DB diagram not entity/POCO diagram.

fail

re: POCO in the Entity Framework: Part 1 - The Experience

Thanigainathan — Sun, 24 May 2009 17:09:24 GMT

Hi,

Very nice post Faisal. So you are making it completely persistent one.

Cheers!

Thani

re: POCO in the Entity Framework: Part 1 - The Experience

Savante — Mon, 25 May 2009 16:33:22 GMT

I don't understand why i have to provide a context implementation. Since I have a diagram definition, the framework must know how make the entity tracking using proxies without define ObjectSet<T>. I think that EF must use more the model definition to manage entities. By the momen, I prefer the NHibernate solution in this way.

re: POCO in the Entity Framework: Part 1 - The Experience

Dmitry — Tue, 26 May 2009 01:46:13 GMT

@Savante,

I don't think really have to "implement" the context implementation. If you look at the code the sample context does two things.

1. Provides connection and container names into the base ObjectContext object.

2. Caches an instance of the ObjectSet<T> in a public property for each entity type.

There is really nothing model specific in it. Both the issues above could be resolved by implementing a context that works with any EF 4.0 projects.

The derived object would get connection and container data from Web.Config and the mapping metadata and would pass it into the ObjectContext.

It would also implement implement a method (for example) Set<T>() which would initialize and cache in a hashtable an ObjectSet<T> instance for each entity type.

This context could be reused in any application without having to manually implement anything; and you would be able to access entity sets using "context.Set<Category>()".

P.S. I agree with nhibernateuser that it would make more sense to generate designer mappings from the model and not the other way around.

Weekly Web Nuggets #65

Code Monkey Labs — Tue, 26 May 2009 18:25:14 GMT

Pick of the week: IP and Non-Competes for Employees General Visual Studio 2010 Beta 1 : Go get the first beta of the next version of Visual Studio! Microsoft Set To Announce Commercial Availability of Windows Azure at PDC This Year : Alin Irimie has some

Programmer Speaks:- Entity Framework 4.0 features of interest to me as a Standard Programmer

Learnings.. — Wed, 27 May 2009 03:46:40 GMT

Going through the changes in Entity Framework I must say MSFT really does take in feedback. I have been

Programmer Speaks:- Entity Framework 4.0 features of interest to me as a Standard Programmer

Learnings.. — Thu, 28 May 2009 01:50:19 GMT

Going through the changes in Entity Framework I must say MSFT really does take in feedback. I have been

re: POCO in the Entity Framework: Part 1 - The Experience

divega@microsoft.com — Thu, 28 May 2009 08:12:55 GMT

@Brendan,

We don't have plans for supporting partially mapped entity types in this release, but I certainly would like to hear what makes this feature important to you.

-Diego

re: POCO in the Entity Framework: Part 1 - The Experience

Alexey Shirshov — Thu, 28 May 2009 09:48:07 GMT

What about references in POCO types to general entities and vice versa.

POCO in the Entity Framework : Part 2 – Complex Types, Deferred Loading and Explicit Loading

ADO.NET team blog — Thu, 28 May 2009 19:03:56 GMT

In my post last week on the POCO Experience in Entity Framework , I covered the fundamentals of POCO

re: POCO in the Entity Framework: Part 1 - The Experience

Hemanshu Bhojak — Fri, 29 May 2009 22:47:53 GMT

Is it possible to use the entity framework 4.0 in Visual Studio 2008? I hope MS does not expect us to keep buying a new IDE every 2 yrs ;)

POCO in the Entity Framework - The Experience

Web开发技术 — Sun, 31 May 2009 05:16:15 GMT

Last week I mentioned in the sneak preview on POCO that support for POCO entities is one of the new capabilities

实体框架中的POCO体验

Web开发技术 — Sun, 31 May 2009 06:49:52 GMT

【译者按】 Entity Framework 1.0 发布也有一段时间了，但感觉用的人很少。其中一个很大的原因，也许就是不支持POCO。要知道，Entity Framework 1.0的做法是让你的实体从EF的基类继承而来

re: POCO in the Entity Framework: Part 1 - The Experience

Ngoc Luu — Mon, 01 Jun 2009 06:14:09 GMT

Will this code supported in this version of EF?

var products = from p in db.Products

select new Product

{

Id = n.Id,

Name = n.Name

};

I played with VS2010 Beta1 and this exception still occured while it is valid in LINQ to SQL:

"The entity or complex type 'Demo.Product' cannot be constructed in a LINQ to Entities query."

#.think.in infoDose #31 (24th May - 1st June)

#.think.in — Mon, 01 Jun 2009 16:12:42 GMT

#.think.in infoDose #31 (24th May - 1st June)

Entity Framework 4 Persistence-Ignorance First Look

VS2010学习 — Wed, 03 Jun 2009 18:41:59 GMT

Introduction: From the moment I put my hands on Visual Studio.Net 2010 Beta 1 and I’m targeting EF4

Programmer Speaks:- Entity Framework 4.0 features of interest to me as a Standard Programmer

VS2010学习 — Thu, 04 Jun 2009 13:37:22 GMT

Going through the changes in Entity Framework 4.0 I must say MSFT really does take in feedback. I have

re: POCO in the Entity Framework: Part 1 - The Experience

Marcelo — Fri, 05 Jun 2009 10:29:15 GMT

Can you, please, write a complete sample of generic repository and unit of work together, using EF.4.0

Code Only

Entity Framework Design — Wed, 10 Jun 2009 23:06:45 GMT

There are currently two ways to get Entity Framework apps up and running, we call these Database First

re: POCO in the Entity Framework: Part 1 - The Experience

Alexander Gornik — Sat, 13 Jun 2009 01:27:57 GMT

Hi. I've just tried the feature. Why can't i have some mapped properties in a base class and map to it's child where other mapped properties are contained?

i keep getting " The required property 'Name' does not exist on the type 'EFTest.User2'. " while the property is just in the base class (if i override it it works ok). I understand why linq to sql can't support such a scenario, but can't see a reason why you don't.

Can't you tune up you BindingFlags in the convention mapper ? :)

Code Only

VS2010学习 — Mon, 15 Jun 2009 04:23:27 GMT

  There are currently two ways to get Entity Framework apps up and running, we call these Database

Using Repository and Unit of Work patterns with Entity Framework 4.0

ADO.NET team blog — Wed, 17 Jun 2009 02:08:47 GMT

If you have been watching this blog, you know that I have been discussing the various aspects of POCO

A Quest With EF 4.0 (Entity Framework) And NHibernate Part 2

berniea — Thu, 18 Jun 2009 10:05:53 GMT

Usually I don’t really like generated stuff, somehow it seems like I always reach a certain point where

re: POCO in the Entity Framework: Part 1 - The Experience

paul — Sun, 12 Jul 2009 18:43:58 GMT

This looks like a great step forward (finally allowing POCOs for domain models w/ EF). I'm curious as to why properties cannot be virtual, though. Unless I misread.

NHibernate does it exactly the opposite way, where by default your properties should all be virtual to make it so they can generate subclassed proxies more easily and inject lazy loading and such.

re: POCO in the Entity Framework: Part 1 - The Experience

radyo dinle — Sun, 19 Jul 2009 17:38:41 GMT

I meant Col1 (in my above question) for the POCO property!

re: POCO in the Entity Framework: Part 1 - The Experience

Muhammad Mosa — Wed, 05 Aug 2009 01:47:55 GMT

uni-directional relationships is supported, the only restriction is that I should delete the related end navigation property that is not needed! but how I can do so?

re: POCO in the Entity Framework: Part 1 - The Experience

Linus Li — Tue, 10 Nov 2009 16:52:32 GMT

It is very good short paper and get the point precisely. Nobody complains "The unit tests are failed!". Pops up "InvalidOperationException was unhandled by user code". The solution is to add "Microsoft.CSharp" into the reference of NorthwindModel.

re: POCO in the Entity Framework: Part 1 - The Experience

POCO — Wed, 02 Dec 2009 11:12:47 GMT

When try to test the example I'm always getting an ArgumentException in Public NorthwindContext() : base("name=NorthwindEntities" , "NorthwindEntities") telling me that the specified named connection is either not found in configuration, not intended to be used with the EntityClient provider, or not valid.

How can I correct the problem and using the example code?

re: POCO in the Entity Framework: Part 1 - The Experience

Craig Richards — Sun, 13 Dec 2009 02:43:44 GMT

When selecting Category and Product for your model it is important to note that CategoryID needs to be removed from the Product table otherwise you get a MetadataException. The issue is because you POCO Product class does not define the property CategoryID