Will DistinctBy be supported in Filtered Include?

[smarts]

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Is it on the roadmap to support more operations in Filtered Includes? I'm specifically wanting to use OrderByDescending (currently supported) + DistinctBy (currently unsupported) to get multiple max values.

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I'm using comments instead of actual EF Core configuration/attribution
Ex:

public class ParentEntity
{
  public long Id { get; set; }
  // owned entities
  public List<ChildEntityRevision> ChildEntityRevisions { get; set; }
  // I want the ability to do this 👇🏽 in a Filtered Include
  public IEnumerable<ChildEntityRevision> CurrentRevisions
    => ChildEntityRevisions.OrderByDescending(x => x.Version).DistinctBy(x => x.StableKey);
  // if the former is enabled then this 👇🏽 is trivial to also do via filtered include with an extra `Where` and `Take(1)`
  public ChildEntityRevision? GetCurrentRevisionOrDefault(long stableKey)
    => CurrentRevisions.SingleOrDefault(x => x.StableKey == stableKey);
}

public class ChildEntityRevision
{
  public long StableKey { get; set; }
  // increases with each new revision 
  public long Version { get; set; }
}

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[roji]

DistinctBy isn't currently supported by EF in any context, outside or inside of filtered includes - #27470 tracks that.

Distinct (without By) is supported, but not within filtered Include; I've opened #31562 to track that.

[smarts]

@roji thanks for creating that, I've went ahead and upvoted it.
Out of curiosity, do you know if there's already an issue for using GroupBy (in my case with a nested OrderByDescending(…).Take(1) or OrderByDescending(…).First()) in a filtered include? I'm not sure if that would be more palatable to implement or not, but that's another way to accomplish what I want.

[roji]

Not as far as I know... That may be a bit much within filtered include...

[smarts]

Got it. I'll close this issue now and we'll see what happens with the 2 issues you mentioned above. Thanks again!