Mahesh Bhatnagar

$查找

db.demo2.aggregate(
    {
      $lookup:
         {
           from: "demo1",
           let: { recordName: "$name"},
           pipeline: [
              { $match:
                 { $expr:
                    { $and:
                       [
                         { $eq: [ "$$recordName",  "$name" ] },
                       ]
                    }
                 }
              },
           ],
           as: "testInform"
         }

    }
    )