Python MongoDB - Query

Advertisements

Previous Page
Next Page  

While retrieving using find() method, you can filter the documents using the query object. You can pass the query specifying the condition for the required documents as a parameter to this method.

Operators

Following is the list of operators used in the queries in MongoDB.

Operation Syntax Example
Equality {"key" : "value"} db.mycol.find({"by":"tutorials point"})
Less Than {"key" :{$lt:"value"}} db.mycol.find({"likes":{$lt:50}})
Less Than Equals {"key" :{$lte:"value"}} db.mycol.find({"likes":{$lte:50}})
Greater Than {"key" :{$gt:"value"}} db.mycol.find({"likes":{$gt:50}})
Greater Than Equals {"key" {$gte:"value"}} db.mycol.find({"likes":{$gte:50}})
Not Equals {"key":{$ne: "value"}} db.mycol.find({"likes":{$ne:50}})

Example1

Following example retrieves the document in a collection whose name is sarmista.

from pymongo import MongoClient

#Creating a pymongo client
client = MongoClient('localhost', 27017)

#Getting the database instance
db = client['sdsegf']

#Creating a collection
coll = db['example']

#Inserting document into a collection
data = [
   {"_id": "1001", "name": "Ram", "age": "26", "city": "Hyderabad"},
   {"_id": "1002", "name": "Rahim", "age": "27", "city": "Bangalore"},
   {"_id": "1003", "name": "Robert", "age": "28", "city": "Mumbai"},
   {"_id": "1004", "name": "Romeo", "age": "25", "city": "Pune"},
   {"_id": "1005", "name": "Sarmista", "age": "23", "city": "Delhi"},
   {"_id": "1006", "name": "Rasajna", "age": "26", "city": "Chennai"}
]
res = coll.insert_many(data)
print("Data inserted ......")

#Retrieving data
print("Documents in the collection: ")
for doc1 in coll.find({"name":"Sarmista"}):
   print(doc1)

Output

Data inserted ......
Documents in the collection:
{'_id': '1005', 'name': 'Sarmista', 'age': '23', 'city': 'Delhi'}

Example2

Following example retrieves the document in a collection whose age value is greater than 26.

from pymongo import MongoClient

#Creating a pymongo client
client = MongoClient('localhost', 27017)

#Getting the database instance
db = client['ghhj']

#Creating a collection
coll = db['example']

#Inserting document into a collection
data = [
   {"_id": "1001", "name": "Ram", "age": "26", "city": "Hyderabad"},
   {"_id": "1002", "name": "Rahim", "age": "27", "city": "Bangalore"},
   {"_id": "1003", "name": "Robert", "age": "28", "city": "Mumbai"},
   {"_id": "1004", "name": "Romeo", "age": "25", "city": "Pune"},
   {"_id": "1005", "name": "Sarmista", "age": "23", "city": "Delhi"},
   {"_id": "1006", "name": "Rasajna", "age": "26", "city": "Chennai"}
]
res = coll.insert_many(data)
print("Data inserted ......")

#Retrieving data
print("Documents in the collection: ")
for doc in coll.find({"age":{"$gt":"26"}}):
   print(doc)

Output

Data inserted ......
Documents in the collection:
{'_id': '1002', 'name': 'Rahim', 'age': '27', 'city': 'Bangalore'}
{'_id': '1003', 'name': 'Robert', 'age': '28', 'city': 'Mumbai'}
Advertisements