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for post in db.datasets.find({"test_set":"abc"}).sort("abc",pymongo.DESCENDING).skip((page-1)*num).limit(num):
How do I get the count()?
Since pymongo version 3.7.0 and above count() is deprecated. Instead use Collection.count_documents. Running cursor.count or collection.count will result in following warning message:
DeprecationWarning: count is deprecated. Use Collection.count_documents instead.
To use count_documents the code can be adjusted as follows
import pymongo
db = pymongo.MongoClient()
col = db[DATABASE][COLLECTION]
find = {"test_set":"abc"}
sort = [("abc",pymongo.DESCENDING)]
skip = 10
limit = 10
doc_count = col.count_documents(find, skip=skip)
results = col.find(find).sort(sort).skip(skip).limit(limit)
for doc in result:
   //Process Document
Note: count_documents method performs relatively slow as compared to count method. In order to optimize you can use collection.estimated_document_count. This method will return estimated number of docs(as the name suggested) based on collection metadata.
                This is an annoying change. Now, instead of making find request, and then .counting the result Cursor, you need to make two calls, one to run count_documents, and one to get the actual results. This seems wasteful with complex filters (I don't know if it actually is). For small results sets len(list(cursor)) could work, but that's going to be a terrible idea on a large result set...
– naught101
                Nov 2, 2020 at 6:39
                for copy pasters, using the var name filter will redefine python filter function, could result in unexpected behaviour of your code
– toing_toing
                Jan 24, 2021 at 0:08
If you want results_count to ignore your limit():
results = db.datasets.find({"test_set":"abc"}).sort("abc",pymongo.DESCENDING).skip((page-1)*num).limit(num)
results_count = results.count()
for post in results:
If you want the results_count to be capped at your limit(), set applySkipLimit to True:
results = db.datasets.find({"test_set":"abc"}).sort("abc",pymongo.DESCENDING).skip((page-1)*num).limit(num)
results_count = results.count(True)
for post in results:
                results_count = results.count(True) docs.mongodb.org/manual/reference/method/cursor.count  I think I misread your post though.  I stopped at the first for loop. I see now that you have that mentioned.  Sorry for flying by the seat of my pants.
– Jake
                Nov 8, 2013 at 7:20
Not sure why you want the count if you are already passing limit 'num'. Anyway if you want to assert, here is what you should do.
results = db.datasets.find({"test_set":"abc"}).sort("abc",pymongo.DESCENDING).skip((page-1)*num).limit(num)
results_count = results.count(True)
That will match results_count with num
Cannot comment unfortuantely on @Sohaib Farooqi's answer... Quick note: although, cursor.count() has been deprecated it is significantly faster, than collection.count_documents() in all of my tests, when counting all documents in a collection (ie. filter={}). Running db.currentOp() reveals that collection.count_documents() uses an aggregation pipeline, while cursor.count() doesn't. This might be a cause.
This thread happens to be 11 years old. However, in 2022 the 'count()' function has been deprecated. Here is a way I came up with to count documents in MongoDB using Python. Here is a picture of the code snippet. Making a empty list is not needed I just wanted to be outlandish. Hope this helps :). Code snippet here.
The thing in my case relies in the count of matched elements for a given query, and surely not to repeat this query twice:  
one to get the count, and

two to get the result set.  
no way
I know the query result set is not quite big and fits in memory, therefore, I can convert it to a list, and get the list length.
This code illustrates the use case:
# pymongo 3.9.0
while not is_over:
  it = items.find({"some": "/value/"}).skip(offset).size(limit)
  # List will load the cursor content into memory
  it = list(it)
  if len(it) < size:
    is_over = True
  offset += size
If you want to use cursor and also want count, you can try this way
# Have 27 items in collection
db = MongoClient(_URI)[DB_NAME][COLLECTION_NAME]
cursor = db.find()
count = db.find().explain().get("executionStats", {}).get("nReturned")
# Output: 27
cursor = db.find().limit(5)
count = db.find().explain().get("executionStats", {}).get("nReturned")
# Output: 5
# Can also use cursor
for item in cursor:
You can read more about it from https://pymongo.readthedocs.io/en/stable/api/pymongo/cursor.html#pymongo.cursor.Cursor.explain
if you wants all the records count(without any filter) in a collection then use this:
from pymongo import MongoClient
cl = pymongo.MongoClient(host="localhost", port=27017)
db = cl["database_name"]
print(db.get_collection("collection_name").estimated_document_count())
        
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