SELECT c.id, childUnit
FROM c JOIN childUnit IN c.structure.childUnits
WHERE c.structure.id = "7d2d5d3f-0c82-4910-aa0b-54d8067588a3"
    AND childUnit.id = "3fb44416-8fa8-4b60-8c0c-03b333d176f7"*

SELECT c.id, childUnit
FROM c JOIN childUnit IN c.childUnits
WHERE c.id = "7d2d5d3f-0c82-4910-aa0b-54d8067588a3"
    AND childUnit.id = "3fb44416-8fa8-4b60-8c0c-03b333d176f7"*