Python MongoDB Find
In MongoDB we use the find() and find_one() methods to find data in a collection.
Just like the SELECT statement is used to find data in a table in a MySQL database.
Find One
To select data from a collection in MongoDB, we can use the
find_one() method.
The find_one() method returns the first
occurrence in the selection.
Example
Find the first document in the customers collection:
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
x = mycol.find_one()
print(x)
Run example »
Find All
To select data from a table in MongoDB, we can also use the
find() method.
The find() method returns all
occurrences in the selection.
The first parameter of the find() method
is a query object. In this example we use an empty query object, which selects
all documents in the collection.
No parameters in the find() method gives you the same result as SELECT * in MySQL.
Example
Return all documents in the "customers" collection, and print each document:
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
for x in mycol.find():
print(x)
Run example »
Return Only Some Fields
The second parameter of the find() method
is an object describing which fields to include in the result.
This parameter is optional, and if omitted, all fields will be included in the result.
Example
Return only the names and addresses, not the _ids:
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
for x in mycol.find({},{ "_id": 0, "name": 1, "address": 1 }):
print(x)
Run example »
You are not allowed to specify both 0 and 1 values in the same object (except if one of the fields is the _id field). If you specify a field with the value 0, all other fields get the value 1, and vice versa:
Example
This example will exclude "address" from the result:
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
for x in mycol.find({},{ "address": 0 }):
print(x)
Run example »
Example
You get an error if you specify both 0 and 1 values in the same object (except if one of the fields is the _id field):
import pymongo
myclient = pymongo.MongoClient("mongodb://localhost:27017/")
mydb = myclient["mydatabase"]
mycol = mydb["customers"]
for x in mycol.find({},{ "name": 1, "address": 0 }):
print(x)
