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MongoDB (PyMongo) Pagination with distinct not giving consistent result

I am trying to achieve pagination with distinct using pymongo.
I have records
{
name: string,
roll: integer,
address: string,
.
.
}
I only want name for each record, where name can be duplicate, so i want distinct name with pagination.
result = collection.aggregate([
{'$sort':{"name":1}},
{'$group':{"_id":"$name"}},
{'$skip':skip},
{'$limit':limit}
])
Problem is, with this query, each time I query I get different result for same page number
Looked into this answer
Distinct() command used with skip() and limit()
but didn't help in my case.
How do I resolve this.
Thanks in advance!

I've tried to sort after the group and it seems to solve the problem
db.collection.aggregate([
{
"$group": {
"_id": "$name"
}
},
{
"$sort": {
"_id": 1
}
},
{
"$skip": 0
},
{
"$limit": 1
}
])
try it here

Update nested Python list key using pop

I have a json file called pool.json which contains this:
{
"pools": {
"$poolId": {
"nodes": {
"$nodeId": {
"bcm": {
"address": {
"ip": "10.10.10.10"
},
"password": "ADMIN",
"username": "ADMIN"
}
}
}
}
}
}
This is my Python code:
pool_id = ['123456']
json_pool = json.loads(read_json_file('pool.json'))
for i in pool_id:
json_pool['pools'][i] = json_pool.pop(['pools']['$poolId'])
print('json_pool: %s' % json_pool)
I'm trying to update $poolId with the value in pool_id(I know I've only got one pool_id. I just want to get this piece working before I do anything else). Ive been trying to do this with pop but am having no success when it's nested as in this case. I can get it working when I want to change a top level key. What am I doing wrong?

I think you want to execute json_pool['pools'].pop('$poolId') instead of json_pool.pop(['pools']['$poolId']).

Issue in updating elastic search field

This how my result source looks like.
{"_source": {"Name": "Where's My Crown Angry birds 3","movie_id":69}}
I need to update the Name field as "'Where's My Crown'". I used the following query:
{"script": {"inline": "ctx._source.Name='Where's My Crown'","lang": "painless"},"query": {"match": {"movie_id": 69}}}
But I got this error:
{'type': 'illegal_argument_exception', 'reason': "unexpected token ['s'] was expecting one of [{<EOF>, ';'}]."}**
Please help me to fix this.

This is because of the fact that there is a single quote in "Where's My Crown" and that interferes with the single quotes around the whole string.
Consider doing it like this (using params) instead:
{
"script": {
"inline": "ctx._source.Name = params.newName",
"params": {
"newName": "Where's My Crown"
},
"lang": "painless"
},
"query": {"match": {"movie_id": 69}}
}

I tried the solution below and it also worked for me:
Replace
'Where's My Crown'
with
\"Where's My Crown\"
So in my case (in JavaScript, not Python, but I think it would work similarly):
const script = Object.entries(newBody).reduce((prev, [key, value]) => {
return `${prev} ctx._source.${key}=\"${value}\";`;
}, '');

Pymongo document query for conversion to INI file

{
"name":"food",
"core":{
"group":{
"carbs":{
"USA":{
"breakfast":"potatoes",
"dinner":"pasta"
},
"europe":{
"breakfast":"something",
"dinner":"something"
}
},
"dessert":{
"USA":{
"breakfast":"potatoes",
"dinner":"pasta"
},
"europe":{
"breakfast":"something",
"dinner":"something"
}
},
"veggies":{
"USA":{
"breakfast":"potatoes",
"dinner":"pasta"
},
"europe":{
"breakfast":"something",
"dinner":"something"
}
}
}
}
}
I am trying to find a way to just return the core groups (carbs, dessert, and veggies).
i have the following python code but it returns all the values in the document, when i am only interested in the core.group
data = collection.foodie.find({"name":"food"},{"name":False, '_id':False, "core.groups.carbs.europe":False, "core.groups.dessert.europe":False, "core.groups.veggies.europe":False
The end result is an INI file with the type of group as the section name for USA only like below, which is why I am looking for a way to just list the groups so i can dynamically look for the actual values stored for when I do not know the groups (have them hardcoded like core.group.dessert.europe)
[carbs]
breakfast=potatoes
dinner=pasta
[dessert]
breakfast=potatoes
dinner=pasta
[veggies]
breakfast=potatoes
dinner=pasta

Python Falcon filtering through URL

I have a small API that i'm working on, everything works ok, all my requests do what they are supposed to but when I try to filter results through the URL query for some reason it works for id but not for device field.
def on_get(self, req, resp):
"""Handles GET requests"""
if req.get_param("id"):
result = {'location': r.db(PROJECT_DB).table(PROJECT_TABLE).get(req.get_param("id")).run(db_connection)}
elif req.get_param("device"):
result = {'location': r.db(PROJECT_DB).table(PROJECT_TABLE).get(req.get_param("device")).run(db_connection)}
else:
location = r.db(PROJECT_DB).table(PROJECT_TABLE).run(db_connection)
result = {'locations': [i for i in location]}
resp.body = json.dumps(result)
example http://localhost:8000/location?id=(some random id) this will work
but if i do http://localhost:8000/location?device=(some device) this will not work, returns null
So could anyone tell me what am I doing wrong? or better yet if anyone knows a better way to filter using the URL?
Note: I am using rethinkdb
EDIT:
This is what I have normally:
{
"locations": [
{
"id": "4bf4b94f-747a-42db-9d54-a8399d995025",
"location": "gps coords",
"device": "Device 2"
},
{
"id": "b5cce561-37d2-42e7-86e4-a31c008b0af2",
"location": "gps coords",
"device": "Device 1"
},
{
"id": "bebba7cf-710c-4ee8-ad69-2d58174d4e02",
"location": "gps coords",
"device": "Device 1"
},
{
"id": "e928f84b-60ff-40f3-b839-920bc99e5480",
"location": "gps coords",
"device": "Device1"
}
]
}
Filtering by id works ok, but not by device which is weird

I found the answer to this problem, the reason why it did not war was because rethinkdb only gets via primary key on the get query
result = {'location': r.db(PROJECT_DB).table(PROJECT_TABLE).get(req.get_param("device")).run(db_connection)}
so what I should have done was to filter the results by what I wanted like this and it would have worked
result = {'location': list(r.db(PROJECT_DB).table(PROJECT_TABLE).filter({'device': param}).run(db_connection))}
Thanks for the help everyone and hope this answer helps.