📘 讲座材料
| 《Practical MongoDB Aggregations》在线版 | https://www.practical-mongodb-aggregations.com/ |
| 《Practical MongoDB Aggregations》印刷版 | Packt Publishing |
| MongoDB 大学课程 | https://learn.mongodb.com/courses/mongodb-aggregation |
| MongoDB 聚合管道文档 | https://www.mongodb.com/docs/manual/core/aggregation-pipeline/ |