MongoDB is a cross-platform, document-oriented database that works on the concept of collections and documents. MongoDB offers high speed, high availability, and high scalability.

Accessing a Collection

1) Getting a list of collection:For getting a list of a MongoDB database's collections list_collection_names() method is used. This method returns a list of collections.
Syntax:

list_collection_names()

 
Example:
 

Sample Database:

frompymongoimportMongoClient# create an client instance of the# MongoDB classmo_c=MongoClient()# create an instance of 'some_database'db=mo_c.GFG# get a list of a MongoDB database's# collectionscollections=db.list_collection_names()print("collections:",collections,"\n")

Output:

collections: ['Geeks']

2) Check if the collection exist or not:To check if the collection attribute exists for the database use hasattr() method. It returns true if the collection is in database otherwise returns false. 

Syntax:hasattr(db, 'collectionname')

Parameters:
db:It is database object. 
collectionname:It is the name of the collection. 

Example:

frompymongoimportMongoClient# create an client instance of# the MongoDB classmo_c=MongoClient()# create an instance of 'some_database'db=mo_c.GFG# check collection is exists or notprint(hasattr(db,'Geeks'))

Output:

True

3) Accessing a Collection:To access a MongoDB collection name use the below syntax. 
 

Syntax:

database_object.Collectionnameordatabase_object["Collectionname"]

Note:Database_object["Collectioname"] can be useful in the case where the name of the collection contains a space in between them i.e. in cases like database_object["Collection name"].
Example:

frompymongoimportMongoClient# create an client instance of# the MongoDB classmo_c=MongoClient()# create an instance of 'some_database'db=mo_c.GFGcol1=db["gfg"]print("Collection:",col1)

 
Output: 

Collection: Collection(Database(MongoClient(host=['localhost:27017'], document_class=dict, tz_aware=False, connect=True), 'GFG'), 'gfg')

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