We need to add support for the SubDoc API to allow for lookupIn and mutateIn operations. These allows for partial retrieval of a documents properties, as well as selective updating of a documents properties on the server without the need to retrieve the entire document.
sub-document operations can be used to efficiently access parts of documents. Sub-document operations may be quicker and more network-efficient than full-document operations such as upsert, update and get because they only transmit the accessed sections of the document over the network. Sub-document operations are also atomic, allowing safe modifications to documents with built-in concurrency control.
While full-document retrievals retrieve the entire document and full document updates require sending the entire document, sub-document retrievals only retrieve relevant parts of a document and sub-document updates only require sending the updated portions of a document. You should use sub-document operations when you are modifying only portions of a document, and full-document operations when the contents of a document is to change significantly.