MongoDB中多表关联查询(
1.使用aggregate 查看表数据
db.getCollection('reports').aggregate([ { $lookup: { from: "process", localField: "sid", foreignField: "sid", as: "docs" } }, {$match:{"industry_info.oid":21,sync:2}}, {$project:{"docs":1}} ])
参考资料:https://www.cnblogs.com/huangxincheng/p/5728791.html