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  1. C# Driver
  2. CSHARP-4738

LINQ3: Support pipeline in $lookup translations (Join/GroupJoin)

    • Type: Icon: Improvement Improvement
    • Resolution: Unresolved
    • Priority: Icon: Unknown Unknown
    • None
    • Affects Version/s: 2.20.0
    • Component/s: LINQ3

      I'm trying to do a GroupJoin between two aggregation queries.

      i.e. Collection1.OfType<TypeA>().GroupJoin(Collection2.OfType<TypeB>(), ...)

      Trying to do this fails currently in ExtensionMethods.GetCollectionInfo as the inner expression is not considered constant.

      $lookup looks to support this via the 'pipeline' parameter however there doesn't look to be any way to supply this through LINQ Join/GroupJoin translations.

       

      I'm not sure if it's possible to add this support, I guess it would need to separate out the collection (constant expression) from the pipeline and forward the pipeline as the lookup parameter?

       

      Thanks

            Assignee:
            robert@mongodb.com Robert Stam
            Reporter:
            alistair.steele@trapdoorlabs.uk Alistair Steele
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              Created:
              Updated: