mongodb学习经验

1、ObjectId与String相互转换

ObjectId类型 —→ String类型
这个非常简单，直接强制类型转换就可以了
_id = str(ObjectId('类型'))

String类型 —→ ObjectId类型
from bson.objectid import ObjectId
_id = ObjectId("字符串")

2、连接数据库

# 一、AsyncIOMotorClient 异步
DB_CLIENT = AsyncIOMotorClient('127.0.0.1', 27017)
db = DB_CLIENT['xy']  # 库名称

# 二、pymongo 同步
server = "mongodb://127.0.0.1:27017"
conn = pymongo.MongoClient(server)
db1 = conn["xy"]
xyuser = db1.get_collection('xyuser')

3、常用

一、ObjectId返回前端后，可以传参过来直接在_id字段使用
async def mongodb(oid: str, request: Request):
    oid = ObjectId('632bd220c66f6b200868ed6c')
    cursor = db.user.find({'_id': {'$eq': oid}})  # 返回cursor
    docs = await cursor.to_list(None)             # 注意cursor的处理
    print(str(docs[0].get('_id')))

二、插入多个值，返回_id列表
    docs = await Userorg.all().values()
    print(docs)
    insert_many = await db.userorg.insert_many(docs)
    print(insert_many.inserted_ids)
    return {'msg': repr(len(insert_many.inserted_ids))}

三、插入和返回多个值
    result = await db.test.insert_many(
        [{'i': i} for i in range(200000)])
    async for document in db.xyuser.find():
        print(document)
    print('inserted %d docs' % (len(result.inserted_ids),))