MongooseJS - 如何找到具有最大值的元素

如何使用MongooseJS找到具有最大值的元素

javascript
const mongoose = require('mongoose');
// 定义模式和模型
const productSchema = new mongoose.Schema({
  name: String,
  price: Number
});
const Product = mongoose.model('Product', productSchema);
// 查询具有最大价格的产品
Product.aggregate([
  {
    $group: {
      _id: null,
      maxPrice: { $max: "$price" }
    }
  },
  {
    $lookup: {
      from: "products",
      localField: "maxPrice",
      foreignField: "price",
      as: "products"
    }
  },
  {
    $unwind: "$products"
  },
  {
    $project: {
      _id: "$products._id",
      name: "$products.name",
      price: "$products.price"
    }
  }
])
.exec((err, result) => {
  if (err) {
    console.log(err);
  } else {
    console.log(result);
  }
});