什么是PyMongo

PyMongo 是一个 Python 库，用于与 MongoDB 数据库进行交互。MongoDB 是一个基于文档的 NoSQL 数据库，提供高性能、可扩展性和灵活的架构。PyMongo 提供了一套工具，使得在 Python 程序中操作 MongoDB 变得简单和高效。

安装PyMongo

PyMongo地址：https://pypi.org/project/pymongo/

pip install pymongo

使用PyMongo

Mongodb语句学习请查看：Mongodb命令大全

连接Mongo

from pymongo import MongoClient

# 连接MongoDB服务器，无账号密码
# client = MongoClient('localhost', 27017)

# 连接MongoDB服务器，账号密码
uri = "mongodb://testuser:123456@localhost:27017/admin?authSource=admin"

# 连接到 MongoDB
client = MongoClient(uri)

# 检查连接
client.admin.command('ping')

选择数据库和集合

# 选择数据库
db = client['myDB']

# 选择集合
collection = db['myTable']

插入数据

# 插入一条数据  insert_one
document = {"name": "Tom", "age": 25, "city": "New York"}
result = collection.insert_one(document)
print(result.inserted_id)       # 返回插入id


# 插入多条数据  insert_many
documents = [
    {"name": "Jerry", "age": 30, "city": "San Francisco"},
    {"name": "Spike", "age": 35, "city": "Los Angeles"}
]
results = collection.insert_many(documents)
print(results.inserted_ids)     # 返回插入ids

查询数据

# 查询单个文档
result = collection.find_one({"name": "Tom"})
print(result)

# 查询多个文档
results = collection.find({"city": "New York"})
for document in results:
    print(document)

更新数据

# 更新单个文档
result = collection.update_one({"name": "Tom"}, {"$set": {"age": 25}})
print(result.modified_count)    # 返回更新影响行数

# 更新多个文档
results = collection.update_many({"city": "New York"}, {"$set": {"city": "NYC"}})
print(results.modified_count)   # 返回更新影响行数

删除数据

# 删除单个文档
result = collection.delete_one({"name": "Tom"})
print(result.deleted_count)     # 返回删除影响行数

# 删除多个文档
results = collection.delete_many({"city": "NYC"})
print(results.deleted_count)    # 返回删除影响行数

聚合操作

# 聚合管道
pipeline = [
    {"$match": {"city": "San Francisco"}},
    {"$group": {"_id": "$city", "average_age": {"$avg": "$age"}}}
]

# 执行聚合
results = collection.aggregate(pipeline)
for result in results:
    print(result)

索引操作

from pymongo import MongoClient, ASCENDING

# 连接MongoDB服务器，账号密码
uri = "mongodb://testuser:123456@localhost:27017/admin?authSource=admin"

# 连接到 MongoDB
client = MongoClient(uri)

# 检查连接
client.admin.command('ping')

# 选择数据库和集合
collection  = client['mydb']['users']

# 创建索引
collection.create_index([("name", ASCENDING)])

# 列出索引
indexes = collection.list_indexes()
for index in indexes:
    print(index)

# 删除索引
collection.drop_index([("name", ASCENDING)])

# 列出索引
indexes = collection.list_indexes()
for index in indexes:
    print(index)