Retrieving information from Pointer field

Question

I'm trying to retrieve a field from a Pointer as suggested on this post but I'm always getting undefined.

This is what my table Publication looks like:

• userId -> User
• subCategoryId -> SubCategory
• title
• description

And my SubCategory table:

• categoryId -> Category
• name
• isActive

And this is my attempt (I only have one row on the table):

var user = Parse.User.current();
var User = Parse.Object.extend("User");
var userQuery = new Parse.Query(User);
userQuery.equalTo("objectId", user.id);

var Publication = Parse.Object.extend("Publication");
var publicationQuery = new Parse.Query(Publication);
publicationQuery.include("subCategoryId");
publicationQuery.matchesQuery("userId", userQuery);        
publicationQuery.find({
    success: function(publications) {
        console.log(publications[0].get("title"));
        // This one returns undefined
        console.log(publications[0].get("subCategoryId"));
    }, error: function(error) {
        // Nothing here as suggested by @adolfosrs
        console.log(error);
    }
});

What I need is:

publications[0].get("subCategoryId").get("name");

But obviously the latter throws:

Uncaught TypeError: Cannot read property 'get' of undefined

Answer 1

If you have Pointers in your parse database like the following, there is no need on working with the objectIds.

The data that you should have is something like this:

Publication:

• user (Pointer <_User>)
• subCategory (Pointer <SubCategory>)
• title (String)
• description (String)

SubCategory:

• category (Pointer <Category>)
• name (String)
• isActive (boolean)

So if you are saving the data as expected the following must work:

var currentUser = Parse.User.current();
var Publication = Parse.Object.extend("Publication");
var publicationQuery = new Parse.Query(Publication);
publicationQuery.equalTo("user", currentUser); 
publicationQuery.include("subCategory");       
publicationQuery.find({
    success: function(publications) {
        console.log(publications[0].get("title"));
        // This one returns undefined
        console.log(publications[0].get("subCategory").get("name");
    }
});