Description

Improve the $unwind operator page. See Scope of Changes for details.

Scope of changes

(some combination/permutations):

• More clearly define the two different unwind argument syntaxes.

• Add multi-stage examples. Check some existing examples in docs for use of unwind. Where appropriate, show the results of each individual stage. Utilize common datasets for multiple examples where we can.

• Order examples such that common use cases appear first.

• For each example, make sure we provide a command to insert the sample documents so users can follow along. Each example should follow the form: Sample Documents, Aggregation, Results.

• Add comments to examples where appropriate.

• Try out different ways to present the multiple syntax. Have examples which show both the Field Path Operand and Document Operand.

• ``includeArrayIndex`` and ``preserveNullAndEmptyArrays`` example section is very long. We can split this into either subsections or tabs.

• In the arguments table, add linkable references. This way we can link to argument descriptions in the copy.

• Double check the language to vet out the unclear/ambiguous/etc.

Impact to Other Docs

Can check other agg pages which use $unwind in examples for inspiration. Can possibly synchronize examples across multiple agg pages if they use the same stages.

MVP (Work and Date)

Resources (Scope or Design Docs, Invision, etc.)