javascript - How to update a property of an object using Parse Cloud Code?

Question

Every Parse Installation object instance in my Parse database has a pointer to a specific user. I have a background job that runs for every user, and what I want to do in this part of the background job is to set the respective user Installation's channel property to ["yesPush"], for push notification targeting purposes.

The way I figured I would do it is by querying for the specific Parse.Installation instance, and then setting its channels property. This doesn't seem to be working however. I'm trying to follow the guidelines in the Parse Cloud Code Docs, but it's either not the correct use case, or I'm not following it correctly.

Code:

var installationQuery = new Parse.Query(Parse.Installation);
installationQuery.equalTo('userId', parentUser);

installationQuery.find().then(function(results) {
  return Parse.Object.set('channels', ["yesPush"]);
});