PyMongo和Mongodb：使用update（）

Question

I am trying to use pymongo to update an existing index:

#!/usr/bin/env python

import pymongo
from pymongo import MongoClient
client = MongoClient()
db = client.alfmonitor
tests = db.tests

post = {
    'name' : 'Blah',
    'active' : True,
    'url' : 'http://www.google.com',
}

tests.insert(post)

tests_list = db.tests.find({'active':True, 'name':'Blah'})
for test in tests_list:
    test['active'] = False
    test.update(
        test,
    )

print '===================================================='

for test in db.tests.find():
    print test #<- when I print out these, active=True is still showing up

I've been trying to follow documentation and examples I have seen on SO but none of them seem to be working for me. Anyone can explain what I'm doing wrong here?

Thanks!

Answer 1

Use this (don't forget to add multi=True if you want to update all matches):

db.tests.update({'active':True, 'name':'Blah'}, {'$set': {'active': False}}, multi=True)

Why your code isn't working:

for test in tests_list:
    # test is of a dict type
    test['active'] = False
    # You are calling the method of dict type
    # that adds all values from dictionary test to dictionary test,
    # so nothing goes to database
    test.update(
        test,
    )

Answer 2

When you want to commit changes made to a retrieved doc, use collection.save instead of update :

test['active'] = False
db.tests.save(test)

Answer 3

Both of these worked for me:

db.tests.update(
    {'active':True, 'name':'Blah'}, 
    {
        '$set': {'active': False}
    },
    multi=True
)


tests_list = db.tests.find({'active':True, 'name':'Blah'})
for test in tests_list:
    test['active'] = False
    db.tests.save(test)

Thanks very much traceur and JonnyHK!