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Python MongoDB Query:
Filter the Result
When finding documents in a collection, you can filter the result by using a query object.
The first argument of the find()
method
is a query object, and is used to limit the search.
Example
Find document(s) with the address "Park Lane 38":
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
myquery = { "address": "Park Lane 38" }
mydoc = mycol.find(myquery)
for x in mydoc:
print(x)
Run example »
Advanced Query
To make advanced queries you can use modifiers as values in the query object.
E.g. to find the documents where the "address" field starts with the letter "S"
or higher (alphabetically), use the greater than modifier:
{"$gt": "S"}
:
Example
Find documents where the address starts with the letter "S" or higher:
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
myquery = { "address": { "$gt": "S" } }
mydoc = mycol.find(myquery)
for x in mydoc:
print(x)
Run example »
Filter With Regular Expressions
You can also use regular expressions as a modifier.
Regular expressions can only be used to query strings.
To find only the documents where the "address" field starts with the letter "S", use the regular
expression {"$regex": "^S"}
:
Example
Find documents where the address starts with the letter "S":
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
myquery = { "address": { "$regex": "^S" } }
mydoc = mycol.find(myquery)
for x in mydoc:
print(x)
Run example »