The Cosmos DB Adapter supports joins of a nested array with its parent document.
Joining Nested Structures
The adapter expects the left part of the join is the array document you want to flatten vertically. This type of query is supported through the Cosmos DB API.
For example, consider the following query from Cosmos DB's restaurants collection:
SELECT "restaurants"."restaurant_id", "restaurants".name, "restaurants.grades".* FROM "restaurants.grades" JOIN "restaurants" WHERE "restaurants".name = 'Morris Park Bake Shop'See Vertical Flattening for more details.