MongoDB Limit Fields to Return

This is done using the projection feature. Some examples:

To find all entries in userAccount but only have the email returned:

db.userAccount.find({},{"email":"1"});

To find all entries in userAccount from city "New York" and only have the email returned:

db.userAccount.find({"city","New York"},{"email":"1"});

0 can be used to exclude the field

More examples and references: http://docs.mongodb.org/manual/tutorial/project-fields-from-query-results/