Projection in Spring Data MongoDB

In MongoDB, Projections are a way to fetch only the required fields of a document from a database. This reduces the amount of data that has to be transferred from database server to client and hence increases performance.

public class User {
    private String id;
    private String name;
    private Integer age;
    // standard getters and setters

Projections Using MongoTemplate

Query query = new Query();
List<User> john = mongoTemplate.find(query, User.class);

Projections Using MongoRepository

@Query(value="{}", fields="{name : 1, _id : 0}")
List<User> findNameAndExcludeId();