navigation properties on derived types

Question

 

Now that "Astoria" has hit RTM, I decided to give it another go. I set up a scenario that I had tried months prior (without success). I didn't get very far this time, either. The error I am confronting is (paraphrasing) "Navigation properties on derived types are not supported...". There was a post on this subject way back in Nov '06 discussing the possibility that this might be supported one day. I guess it didn't make the cut for RTM

 

I suppose most folks wouldn't care too much, but I find this very disappointing. It means that if I'm going to use "Astoria", I have to greatly compromise the design of my entity model.

 

Are there any clever hacks around this limitation? Is there any hope that this limitation will be lifted in some future drop?

 

Thanks,

Daniel

 

 

Answer 1

You are right - this didn't make it for the V1 timeframe. We really wanted to support this so that users can use inheritance in the entity model. This is one of the most important features we are targetting for V2. V1 just went out, so it will be some time before we do a beta/ctp for the next release.

 

Pratik

Answer 2

I appreciate the realistic answer, even if that's not what I wanted to hear. Speaking of "realistic", how about if you folks just hand over the source code, and I'll fix it myself

 

Regards,

Daniel

Answer 3

Hi,  i would like to have a refresh of this answer...  To date, is there a workaround or a CTP that could let us do navigating properties with derived types within astoria?

In clear, is there a CTP for the V2 out yet, if not when will it be?

Thanks!

Answer 4

No no we dont tell you the answer, you have to pay for this kind of support

--------------joking aside

@ Everyone

No CTP as of yet boys and girls. And you know the answer for the question that has the word "when" on it. To spell it out: When it is ready.

You understand the implications of giving the community a time frame.

Nice if they deliver early but a storm of hate if it delivered late.

Daniel Portella Blogger from hell http://undocnet.blogspot.com

Iif this reply has answer your question please mark as the answer.

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Daniel Portella - http://undocnet.blogspot.com - This posting is provided "AS IS" with no warranties, and confers no rights.

Answer 5

Hi Daniel,

With CTP1 not supporting navigation properties on derived types is there any further information you can give us (especially timelines!) regarding this important feature?

Thanks,

Drew Loika

Answer 6

I just ran into this bug myself. I really wish the model would complain about navigation properties on derived types at startup though, as it does for other unsupported stuff like enums etc. I only discovered this discrepancy at run time when an entity set with derived types containing navigation properties was accessed.

This is really a deal-breaker as we're pretty far gone on this project and can't really change the model at this stage (not easily anyway). Is there any workaround?

As for v2, can you at least give us some kinda ball park figure on when we can expect some kinda release containing a fix for this issue?

Thanks,

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Jimit Ndiaye

Answer 7

Does v1.5 CTP2 address this issue?

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Jimit Ndiaye

Answer 8

I've just hit this issue using CTP2, so unfortunately no it doesn't. I've also posted on another thread regarding the problem.

Answer 9

Unfortunately, this feature is not supported in the CTP2 and will not be supported in our next release (Both Dev10 and update to 3.5 SP1). There are no workarounds for this as of now, other than changing the model and moving navigation properties to the base type or the entity type referred to by the set.

We have been tracking this feature on our side, and again, this is something we plan to consider in our future releases. Unfortunately, this is the same thing i said at the start of this mail thread, and it didn't make it in our current release. IMO, this is one of the most asked things for the next release and i am hoping that we can fix it next round. But cannot promise you anything at this point.

Thanks
Pratik

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This posting is provided "AS IS" with no warranties, and confers no rights.

Answer 10

I'm facing the same problem and I noticed that in some cases the database is updated even if the error is always the same (...Navigation properties on derived types are not supported...)

Is this a known behavior?

I'm using wcf data services in the visual studio 2010 beta 2

Answer 11

Hi,

If you can repro that behavior (database gets updated even though the request fails with an error), could you please start another thread on the forums with some more details?

Thanks,

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Vitek Karas [MSFT]

Answer 12

Hello Prathik,

When you mean Dev10, are you saying that this will not be supported in EF 4 as well?

Thanks,

Puneet H

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<Puneet />

Answer 13

Hi,

This is not going to be supported in .NET 4.0 release of WCF Data Services. We know this is a feature lot of people ask for, but to stress that even more, you can go to our connect site and vote on the feature there. https://connect.microsoft.com/dataplatform/content/content.aspx?ContentID=15540&wa=wsignin1.0

Thanks,

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Vitek Karas [MSFT]

Answer 14

Hi,

Arey there any plans to support this scenario in .Net 4.5 which is going to be released as part of VS2010 SP1 next month?

Thanks,

Kowshik Palivela

Answer 15

Hello everybody,

I'm bring bad news.

Visual Studio 2010 SP1 doesn't support derived include either.

That's a big problem because I will have to change all my entity data model.

Let's vote to Microsoft release a hotfix for this.

Include for derived types:

dbContext.DataSet.Include<DerivedType>("NavigationProperty");

or

dbContext.DataSet.Include("NavigationProperty<DerivedType>");

Vote on link below:

http://data.uservoice.com/forums/72025-ado-net-entity-framework-ef-feature-suggestions/suggestions/1249289-include-property-of-derived-classes?ref=title

or

http://data.uservoice.com/forums/72025-ado-net-entity-framework-ef-feature-suggestions/suggestions/1057763-inheritance-eager-loading?ref=title

Let's vote guys. Thanks.

Answer 16

Hi,

Recently we released an updated CTP of the next version of WCF Data Services which includes support for properties on derived types. Give it a try: http://blogs.msdn.com/b/astoriateam/archive/2011/03/09/announcing-wcf-data-services-march-2011-ctp2-for-net4-amp-sl4.aspx

Thanks,

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Vitek Karas [MSFT]