Parse server javascript pointer data extraction

Question

I have parse server which I have this query on

const empList = Parse.Object.extend("EmpList");
const query = new Parse.Query(empList);
query.equalTo("relation", Parse.User.current());

query.find({
      success: (results) => {
        // results.map((each)=>this.data = each.id)
        this.data = results
      },

Parse server has 2 classes ( users and EmpList), there is a pointer in EmpList which points correctly to the current user submitted the employee.The returned data also includes the pointer ( which has a name "relation" ) and I can see the username exists as an object in this fashion

Array [
     Object {
       "createdAt"  "2018-07-05T20 17 45.173Z",
       "name"  "1the latter",
       "objectId"  "D2kThKcg9z",
       "phone"  "111",
       "relation"  Object {
         "ACL"  Object {
           "*"  Object {
             "read"  true,
           },
           "H2rQJxNyTD"  Object {
             "read"  true,
             "write"  true,
           },
         },
         "__type"  "Object",
         "className"  "_User",
         "createdAt"  "2018-07-05T18 43 40.536Z",
         "objectId"  "H2rQJxNyTD",
         "password"  undefined,
         "sessionToken"  "r c45063a034dd81d646bef51ae2055c85",
         "updatedAt"  "2018-07-05T20 17 35.976Z",
         "username"  "1",
       },
       "shift"  "tue",
       "updatedAt"  "2018-07-05T20 22 11.158Z",
     },
   ]

Yet I am unable to extract the username in relation object. please help me do so by data[0].relation.username or data[0].relation().username

Answer 1

Check the query() function on the relation that you can use to get all the object in the relation .

Answer 2

There are two things you can do. The simplest is to eagerly fetch the related object as part of the query using include() ...

const query = new Parse.Query(empList);
query.equalTo("relation", Parse.User.current());
query.include("relation");

(Incidentally, "relation" isn't a great name for that column. A better choice would be something relating to it's meaning, like submittedByUser. Calling it relation is like naming your poodle "Poodle").

The drawback of using include is that it will eagerly fetch all of the related objects on the query, making the query take longer and potentially produce data that you don't need. If you only want the related object on one or a handful of the query results, skip the include() and query the relations individually...

const query = new Parse.Query(empList);
query.equalTo("relation", Parse.User.current());

query.find({
    success: results => {
        // for one or some of the results...
        let submittedByUserRelation = user.relation("relation");
        submittedByUserRelation.query().find({
            success: user => {
                // user.username will be the username
            }
        });