MongoDB：$ lookup返回空数组

猫鼬在创建时将集合名称复数。所以代替

schedule

schedules

{ "$lookup": {  "from": "schedules",  "localField": "_id.id",  "foreignField": "customer.id",  "as": "user_detail"}}

或导入集合并从中提取集合名称

const Schedule = require('/schedules'){ "$lookup": {  "from": Schedule.collection.name,  "localField": "_id.phone",  "foreignField": "customer.phone",  "as": "user_detail"}}