Update/Upsert documents in the memory db. They are found first using
find and then updated. Documents updates can be customized
by using an $update function.
function update(
object fields,
[object update|function $update],
[object options|function $update]
)
arguments
fields type object, document(s) fields to lookupupdate type object, which fields to update on document(s) found$update type function, customizes how to update fieldsoptions type object, modifies how to do the updateoptions. Same they are for find plus
$upsert type boolean, wether to insert if no documents found$update type function, customizer for the update$update(doc, update) arguments
doc document found using fieldsupdate same object given as argumentdefaults
options.$update to merge properties of doc with updatereturns this