MongoDB数据库（6）__motor

2019.7.22:

motor是异步实现python操作数据库的工具。能减少后端访问数据库的延迟。

---

Motor 是一个异步实现的 MongoDB 存储库 Motor 与 Pymongo 的配置基本类似。连接对象就由 MongoClient 变为 AsyncIOMotorClient 了。

一、连接

# 普通连接 client = motor.motor_asyncio.AsyncIOMotorClient('mongodb://localhost:27017') # 副本集连接 client = motor.motor_asyncio.AsyncIOMotorClient('mongodb://host1,host2/?replicaSet=my-replicaset-name') # 密码连接 client = motor.motor_asyncio.AsyncIOMotorClient('mongodb://username:password@localhost:27017/dbname') # 获取数据库 db = client.zfdb # db = client['zfdb'] # 获取 collection collection = db.test # collection = db['test']

二、添加一条记录

async def do_insert():      document = {'name': 'zone','sex':'boy'}      result = await db.test_collection.insert_one(document)      print('result %s' % repr(result.inserted_id)) loop = asyncio.get_event_loop() loop.run_until_complete(do_insert())

三、批量增加记录

async def do_insert():     result = await db.test_collection.insert_many(         [{'name': i, 'sex': str(i + 2)} for i in range(20)])     print('inserted %d docs' % (len(result.inserted_ids),))  loop = asyncio.get_event_loop() loop.run_until_complete(do_insert())

四、查找一条记录

async def do_find_one():     document = await db.test_collection.find_one({'name': 'zone'})     pprint.pprint(document)  loop = asyncio.get_event_loop() loop.run_until_complete(do_find_one())

五、查找多条记录

async def do_find():     cursor = db.test_collection.find({'name': {'$lt': 5}}).sort('i')     for document in await cursor.to_list(length=100):         pprint.pprint(document)  loop = asyncio.get_event_loop() loop.run_until_complete(do_find())  # 添加筛选条件，排序、跳过、限制返回结果数 async def do_find():     cursor = db.test_collection.find({'name': {'$lt': 4}})     # Modify the query before iterating     cursor.sort('name', -1).skip(1).limit(2)     async for document in cursor:         pprint.pprint(document)  loop = asyncio.get_event_loop() loop.run_until_complete(do_find())

六、统计

async def do_count():     n = await db.test_collection.count_documents({})     print('%s documents in collection' % n)     n = await db.test_collection.count_documents({'name': {'$gt': 1000}})     print('%s documents where i > 1000' % n)  loop = asyncio.get_event_loop() loop.run_until_complete(do_count())

七、替换

async def do_replace():     coll = db.test_collection     old_document = await coll.find_one({'name': 'zone'})     print('found document: %s' % pprint.pformat(old_document))     _id = old_document['_id']     result = await coll.replace_one({'_id': _id}, {'sex': 'hanson boy'})     print('replaced %s document' % result.modified_count)     new_document = await coll.find_one({'_id': _id})     print('document is now %s' % pprint.pformat(new_document))  loop = asyncio.get_event_loop() loop.run_until_complete(do_replace())

八、更新指定字段，不会影响到其他内容

async def do_update():     coll = db.test_collection     result = await coll.update_one({'name': 0}, {'$set': {'sex': 'girl'}})     print('更新条数： %s ' % result.modified_count)     new_document = await coll.find_one({'name': 0})     print('更新结果为： %s' % pprint.pformat(new_document))  loop = asyncio.get_event_loop() loop.run_until_complete(do_update())

九、删除置顶记录

async def do_delete_many():     coll = db.test_collection     n = await coll.count_documents({})     print('删除前有 %s 条数据' % n)     result = await db.test_collection.delete_many({'name': {'$gte': 10}})     print('删除后 %s ' % (await coll.count_documents({})))  loop = asyncio.get_event_loop() loop.run_until_complete(do_delete_many())