From 867e161bd7ef815a775b39c21d48cc9fccd5c026 Mon Sep 17 00:00:00 2001
From: Diamond Lewis <findlewis@gmail.com>
Date: Thu, 25 Oct 2018 20:43:13 -0500
Subject: [PATCH 1/2] Support Distinct for special fields

---
 spec/ParseQuery.Aggregate.spec.js             | 25 +++++++++++++++++++
 .../Storage/Mongo/MongoStorageAdapter.js      | 13 +++++-----
 2 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/spec/ParseQuery.Aggregate.spec.js b/spec/ParseQuery.Aggregate.spec.js
index b45aa8e7ef..4330f2dd1b 100644
--- a/spec/ParseQuery.Aggregate.spec.js
+++ b/spec/ParseQuery.Aggregate.spec.js
@@ -1098,6 +1098,31 @@ describe('Parse.Query Aggregate testing', () => {
       .catch(done.fail);
   });
 
+  it('distinct objectId', async () => {
+    const query = new Parse.Query(TestObject);
+    const results = await query.distinct('objectId');
+    expect(results.length).toBe(4);
+  });
+
+  it('distinct createdAt', async () => {
+    const object1 = new TestObject({ createdAt_test: true });
+    await object1.save();
+    const object2 = new TestObject({ createdAt_test: true });
+    await object2.save();
+    const query = new Parse.Query(TestObject);
+    query.equalTo('createdAt_test', true);
+    const results = await query.distinct('createdAt');
+    expect(results.length).toBe(2);
+  });
+
+  it('distinct updatedAt', async () => {
+    const query = new Parse.Query(TestObject);
+    const results = await query.distinct('updatedAt');
+
+    // loadTestData() all have the same updatedAt
+    expect(results.length).toBe(1);
+  });
+
   it('distinct null field', done => {
     const options = Object.assign({}, masterKeyOptions, {
       body: { distinct: 'distinctField' },
diff --git a/src/Adapters/Storage/Mongo/MongoStorageAdapter.js b/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
index bbf6bb95b8..b0e3351ee9 100644
--- a/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
+++ b/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
@@ -710,19 +710,20 @@ export class MongoStorageAdapter implements StorageAdapter {
     schema = convertParseSchemaToMongoSchema(schema);
     const isPointerField =
       schema.fields[fieldName] && schema.fields[fieldName].type === 'Pointer';
-    if (isPointerField) {
-      fieldName = `_p_${fieldName}`;
-    }
+    const transformField = transformKey(className, fieldName, schema);
+
     return this._adaptiveCollection(className)
       .then(collection =>
-        collection.distinct(fieldName, transformWhere(className, query, schema))
+        collection.distinct(
+          transformField,
+          transformWhere(className, query, schema)
+        )
       )
       .then(objects => {
         objects = objects.filter(obj => obj != null);
         return objects.map(object => {
           if (isPointerField) {
-            const field = fieldName.substring(3);
-            return transformPointerString(schema, field, object);
+            return transformPointerString(schema, fieldName, object);
           }
           return mongoObjectToParseObject(className, object, schema);
         });

From 8e5e3dda9cc35e502788db2f3d421961319bef6c Mon Sep 17 00:00:00 2001
From: Diamond Lewis <findlewis@gmail.com>
Date: Fri, 26 Oct 2018 09:34:16 -0500
Subject: [PATCH 2/2] update changelog

---
 CHANGELOG.md                      |  2 +-
 spec/ParseQuery.Aggregate.spec.js | 11 ++++++++---
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 67b1e053a8..3bb7fe55c6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,7 +5,7 @@
 
 #### Improvements:
 * Fixes issue that would prevent users with large number of roles to resolve all of them [@Moumouls]() (#5131, #5132)
-
+* Fixes distinct query on special fields ([#5144](https://github.com/parse-community/parse-server/pull/5144))
 
 ### 3.1.0
 [Full Changelog](https://github.com/parse-community/parse-server/compare/3.0.0...3.1.0)
diff --git a/spec/ParseQuery.Aggregate.spec.js b/spec/ParseQuery.Aggregate.spec.js
index 4330f2dd1b..40502de696 100644
--- a/spec/ParseQuery.Aggregate.spec.js
+++ b/spec/ParseQuery.Aggregate.spec.js
@@ -1116,11 +1116,16 @@ describe('Parse.Query Aggregate testing', () => {
   });
 
   it('distinct updatedAt', async () => {
+    const object1 = new TestObject({ updatedAt_test: true });
+    await object1.save();
+    const object2 = new TestObject();
+    await object2.save();
+    object2.set('updatedAt_test', true);
+    await object2.save();
     const query = new Parse.Query(TestObject);
+    query.equalTo('updatedAt_test', true);
     const results = await query.distinct('updatedAt');
-
-    // loadTestData() all have the same updatedAt
-    expect(results.length).toBe(1);
+    expect(results.length).toBe(2);
   });
 
   it('distinct null field', done => {