MongoDB pymongo模块 更新数据

现在chat集合里有3条数据

import pymongo

mongo_client = pymongo.MongoClient(
    host='192.168.0.112',
    port=27017,
    username="admin",
    password=""
)

mongo_db = mongo_client["db1"]
# 更新数据

res = mongo_db.chat.find()
for i in res:
    print(i)

{'_id': ObjectId('5cb0ba3abd99392b1427c25e')}
{'_id': ObjectId('5cb0bbf9bd993914d8b5d82c'), 'name': 'jack', 'age': 13}
{'_id': ObjectId('5cb0bbf9bd993914d8b5d82d'), 'name': 'mike', 'age': 33}

更新

update_one()

传入前面条件，后面关键词

modified_count ：拿到更新的条数

import pymongo

mongo_client = pymongo.MongoClient(
    host='192.168.0.112',
    port=27017,
    username="admin",
    password=""
)

mongo_db = mongo_client["db1"]
# 更新数据

res = mongo_db.chat.update_one({"age":13},{"$set":{"age":34}})
# modified_count 返回更新的条数
print(res,res.modified_count)

# 返回对象
# <pymongo.results.UpdateResult object at 0x0000000002EDBF08>
# 1代表更新一条数据
#

更新成功

import pymongo

mongo_client = pymongo.MongoClient(
    host='192.168.0.112',
    port=27017,
    username="admin",
    password=""
)

mongo_db = mongo_client["db1"]
# 更新数据

res = mongo_db.chat.find_one({"age":34})
print(res)

# {'_id': ObjectId('5cb0bbf9bd993914d8b5d82c'), 'name': 'jack', 'age': 34}

update_many(): 
更新多条数据

把age>=0的数据 age都改成888

import pymongo

mongo_client = pymongo.MongoClient(
    host='192.168.0.112',
    port=27017,
    username="admin",
    password=""
)

mongo_db = mongo_client["db1"]
# 更新数据

res = mongo_db.chat.update_many(
    {"age":{"$gte":0}},{"$set":{"age":888}}
)
print(res,res.modified_count)

# 返回对象
# <pymongo.results.UpdateResult object at 0x0000000002EDBF08>
# 2代表更新2条数据
#