Mongoose 聚合不会返回不匹配的子文档

Question

我在文档中有子文档。如果任何子文档提供多个条件，我会尝试获取整个文档。除了不显示不匹配的子文档外，它工作正常。

# EXAMPLE DOCUMENT
name: "Sam",
specs: [
  {city: "istanbul", color: "blue"},
  {city: "istanbul", color: "black"},
  {city: "izmir", color: "yellow"}
]

# QUERY
Dudes.aggregate([
    {$unwind: '$specs'},
    {$match: {'specs.city': "istanbul", 'specs.color': "yellow"} }
  ]);

它返回匹配的文档，但在文档中只有匹配的子文档。

# OUTPUT:
name: "Sam",
specs: [
  {city: "izmir", color: "yellow"}
]

谢谢

---

已解决： 感谢 Tushar Gupta

Dudes.find({
   specs: {
    $elemMatch: {
       "city": "istanbul",
       "color": "blue"
    }
   }
})

Answer 1

更新的演示 - https://mongoplayground.net/p/J1GF0ErYNEk

使用 $elemMatch 匹配数组元素内的对象。

db.collection.find({
  specs: {
    $elemMatch: {
      "city": "istanbul",
      "color": "blue"
    }
  }
});

---

演示 - https://mongoplayground.net/p/Wr1L6i2dipP

您可以直接使用$match并删除 {$unwind: '$specs'}

db.collection.aggregate([
  {
    $match: {
      "specs.city": "istanbul",
      "specs.color": "blue"
    }
  }
]);