Query select() ignored for subscriptions / live queries

[interaktivarum]

New Issue Checklist

• [x ] I am not disclosing a vulnerability.
• [x ] I am not just asking a question.
• [x ] I have searched through existing issues.
• [x ] I can reproduce the issue with the latest versions of Parse Server and the Parse JS SDK.

Issue Description

Query select() seems to be ignored when subscribing to a query. The LiveQuerySubscription _select array is correctly populated but returns the full object. I get select() to work properly for q.first() but not for subscriptions.

Steps to reproduce

const q = new Parse.Query('GameSession')
.equalTo('objectId', id)
.select('story')

const sub = await q.subscribe();

sub.on('update', (parseObj) => {
    console.log('Session updated from subscription', parseObj);
});

Actual Outcome

Received attributes, all class fields:

{
    "game": { ... },
    "story": { ... },
    "createdAt": "2026-01-21T10:08:37.086Z",
    "updatedAt": "2026-01-21T13:08:07.580Z",
}

Expected Outcome

Only receive selected fields (e.g. story) and not game field.

{
    "story": { ... },
    "createdAt": "2026-01-21T10:08:37.086Z",
    "updatedAt": "2026-01-21T13:08:07.580Z",
}

Environment

Server

• Parse Server version: 6.2.0
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): : Remote service (Back4App)

Database

• System (MongoDB or Postgres): MongoDB
• Database version: 3.6
• Local or remote host (MongoDB Atlas, mLab, AWS, Azure, Google Cloud, etc): Remote service (Back4App)

Client

• Parse JS SDK version: 8.0.0

[parse-github-assistant]

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[dplewis]

There exist a passing test case for this. Can you write a failing on to replicate your issue?

Parse-SDK-JS/integration/test/ParseLiveQueryTest.js

Line 296 in 7390b44

it('can subscribe to query with fields', async () => {