Python MongoDB – find_one Query
Prerequisites: MongoDB Python Basics
This article focus on the find_one() method of the PyMongo library. find_one()
is used to find the data from MongoDB.
Let’s begin with the find_one() method:
- Importing PyMongo Module: Import the PyMongo module using the command:
from pymongo import MongoClient
If MongoDB is already not installed on your machine you can refer to the guide: Guide to Install MongoDB with Python
- Creating a Connection: Now we had already imported the module, its time to establish a connection to the MongoDB server, presumably which is running on localhost (host name) at port 27017 (port number).
client = MongoClient(‘localhost’, 27017)
- Accessing the Database: Since the connection to the MongoDB server is established. We can now create or use the existing database.
mydatabase = client.name_of_the_database
- Accessing the Collection: We now select the collection from the database using the following syntax:
collection_name = mydatabase.name_of_collection
- Finding in the collection: Now we will find in the database using find_one() function. This function return only one value if the data is found in the database else it returns None. It is ideal for those situations where we need to search for the only one document.
Syntax:
find_one(filter=None, *args, **kwargs)
Example 1:
Sample Database:
# Python program to demonstrate # find_one() method # Importing Library from pymongo import MongoClient # Connecting to MongoDB server # client = MongoClient('host_name','port_number') client = MongoClient( 'localhost' , 27017 ) # Connecting to the database named # GFG mydatabase = client.GFG # Accessing the collection named # gfg_collection mycollection = mydatabase.Student # Searching through the database # using find_one method. result = mycollection.find_one({ "Branch" : "CSE" }) print (result) |
Output:
{‘_id’: 1, ‘name’: ‘Vishwash’, ‘Roll No’: ‘1001’, ‘Branch’: ‘CSE’}
Example 2:
# Python program to demonstrate # find_one() method # Importing Library from pymongo import MongoClient # Connecting to MongoDB server # client = MongoClient('host_name','port_number') client = MongoClient( 'localhost' , 27017 ) # Connecting to the database named # GFG mydatabase = client.GFG # Accessing the collection named # gfg_collection mycollection = mydatabase.Student # Searching through the database # using find_one method. result = mycollection.find_one({ "Branch" : "CSE" }, { '_id' : 0 , 'name' : 1 , 'Roll No' : 1 }) print (result) |
Output:
{'name': 'Vishwash', 'Roll No': '1001'}