Enable more value object scenarios

[AndriySvyryd]

This is a grouping of related issues. Feel free to vote (👍) for this issue to indicate that this is an area that you think we should spend time on, but consider also voting for individual issues for things you consider especially important.

---

Related to #1985

Done in 8.0

• Implement complex types (value objects) #13947
• Only discover complex types when configured through pre-convention model configuration #31344
• Use C# structs or classes as value objects #9906
• Support change tracking and lazy-loading proxies for complex types #31634

Done in 9.0

• GroupBy over complex types #33491
• Allow passing complex type instances to ExecuteUpdate #32058

Backlog

• Complex type collection support #31237
• Allow mapping optional complex properties #31376
• Constructor injection for complex types #31621
• Add relational JSON mapping support for complex types #31252
• Add Cosmos support for complex types #31253
• Support immutable entity updates #11457
• Expand tuples to multiple columns #14661
• Support for complex types projected via optional navigations #31412
• Allow to configure properties on non-collection complex types by using chaining in the lambda expression #31236
• Allow navigations and FK properties on non-collection complex types  #31245
• Allow keys and indexes to use properties on non-collection complex types #31246
• Support complex properties on Owned types #33170
• Add inheritance support for complex types #31250
• Add pre-convention configuration for complex types #31249
• Enable shadow complex properties #31243
• Enable indexer complex properties #31244
• ExecuteUpdate: support partial updating inside JSON documents #28766
• Complex type observable ordered value type collection support #31411
• Complex types: support change tracking notifications #32205
• Add store-generated values support for properties on complex types #31251
• Support value generation for complex properties #31633
• Add entity splitting support for complex types #31248
• Add View, TVF and SqlQuery mapping support for complex types #34627
• Add CUD sproc mapping support for complex types #31235
• Add seed data support for complex types #31254
• Allow service properties on complex types #31247
• Implement value conversions that spread out over multiple columns #31234

[jscarle]

Is there a way we can use the current iteration of this so that we can run it against some of our own value objects to help discover and test for potential issues?

[roji]

@jscarle you should be able to give this a test once 8.0.0-rc1 comes out (IIRC next week).

[jscarle]

@roji Now that RC1 has been released, is there any documentation I can read on how to implement some of these new functionalities?

[roji]

@jscarle you probably want to check out the rc1 blog post which just came out.

[oluatte]

+1.

I for one very much appreciate the gradual coverage of DDD scenarios with EF Core. Looking forward to the day when it is painless to use EF Core for a DDD project.

[Gonnagle]

@AndriySvyryd based on https://learn.microsoft.com/en-us/ef/core/what-is-new/ef-core-9.0/whatsnew it would seem that many of the features listed here have been dropped from the 9.0 milestone, right? Eagerly waiting for #31376 for example and could not spot that from release notes.

[AndriySvyryd]

@Gonnagle While it's unlikely that we are able to deliver all of the originally planned features for 9.0 we'll try to fit as many as practical. It's still too early to say which ones are definitely cut.