pymongo_test_query.py

# Get the database using the method we defined in pymongo_test_insert file 
from pymongo_test_insert import get_database
dbname = get_database()

# Create a new collection
collection_name = dbname["user_1_items"]

item_details = collection_name.find()
for item in item_details:
	# This will give readable output, but KeyError
	print(item['item_name'], item['category'])

###---------------------------------------------------###
### Comment the above 'for loop' & 'print statements' ### 
###       for the next lines of code to work          ###
###---------------------------------------------------###
from pandas import DataFrame

# Convert the dictionary objects to dataframe
items_df = DataFrame(item_details)

# View all items
print(items_df)	

###--------------------------------------------------------###
### Get items of particular category without and with index###
###--------------------------------------------------------###
item_details = collection_name.find({"category" : "food"})
for item in item_details:
	print(item)
	
# Add more data to understand the need for indexing
import pymongo_test_insert_more_items
	
# Create index on category, as an example
category_index = collection_name.create_index("category")

# Execute the previous query again to see the documents scanned (refer to the article)