[{"houses":[{"from":"mine","codekey":"123"},{"from":"Giuglio","codekey":"Giuglio010193"},{"from":"Francesco","codekey":"vatican"}]}]

db.collection.update({/**this will match documents*/houses:{$exists:true}},/**filter*/{/**if match*/$set:{"houses.$[el].codekey":"apple"}},{arrayFilters:[{"el.codekey":"123"}],upsert:true})