mongodb聚合在对象中查找多个ObjectId

Question

我有两个集合，我在MongoDB中有一个集合数据

db.user.insert({"_id" : ObjectId("585d627fe4ff58cb1c456780"), "name":"Alfred"});
db.user.insert({"_id" : ObjectId("585d60b5e4ff58cb1c45677f"), "name":"Bruce"});
db.role.insert({"_id" : ObjectId("585d5f7cdb83cb696b82f2cf"),"status" : "admin"});
db.data.insert(
"security": [
    {"idUser" : ObjectId("585d627fe4ff58cb1c456780"), "idRole" : ObjectId("585d5f7cdb83cb696b82f2cf")},
    {"idUser" : ObjectId("585d60b5e4ff58cb1c45677f"), "idRole" : ObjectId("585d5f7cdb83cb696b82f2cf") }]);

当我执行此条件时，数组返回空

db.data.aggregate([
            { $lookup: {from: "user", localField: "user.idUser", foreignField: "_id", as: "user_admin"} },
            {$unwind:"$user_admin"},
]);

我想把两个填充的字段带到数组中每个对象的属性，我非常感谢任何帮助我的人

Answer 1

为了聚合安全性，您需要将其展开然后查找。此查询应该有效：

db.data.aggregate([
            {$unwind: "$security"},
            {$lookup: {from: "user", localField: "security.idUser", foreignField: "_id", as: "user_admin"}},
            {$unwind:"$user_admin"}
]);