Firebase:如何为嵌套字段添加索引？

Question

我有一个 locations-orders 表，如下所示:

{
  "0BW3H9T3R7HJB" : {
    "orders" : {
      "01750ea0-4980-4bc4-58b2-988c02324e671478636582396" : {
        "created_at" : 1478636560000,
      },
      "01750ea0-4980-4bc4-58b2-988c02324e671478636582483" : {
        "created_at" : 1478636560000,
      }
    }
}

每个位置订单节点都有一个带有多个键/对象的orders节点。这些对象上有一个 created_at 字段。

我将此添加到我的数据库规则中:

{
  "rules": {
    ".read": true,
    ".write": true,
    "users": {
      ".indexOn": "merchantId"
    },
    "merchants": {
      ".indexOn": "locations"
    },
    "locations-orders": {
      ".indexOn": ["orders/created_at"]
    }
  }
}

但是，Firebase 仍然提示我缺少索引:

Using an unspecified index. Consider adding ".indexOn": "created_at" at /locations-orders/1JS53G0TT5ZQD/orders to your security rules for better performance

我应该运行一些东西来创建索引吗？还是写错了？

===更新===

我更改了文件以查看:

{
  "rules": {
    ".read": true,
    ".write": true,
    "users": {
      ".indexOn": "merchantId"
    },
    "merchants": {
      ".indexOn": "locations"
    },
    "locations-orders": {
      "$location_id": {
        ".indexOn": ["orders/created_at", "orders/status_updated_at"]
      }
    }
  }
}

但我仍然收到相同的警告:

Using an unspecified index. Consider adding ".indexOn": "created_at" at /locations-orders/1JS53G0TT5ZQD/orders to your security rules for better performance

Answer 1

如果查看数据结构，/location-order/$orderId 下没有 orders/created_at。

{
  "rules": {
    ".read": true,
    ".write": true,
    "users": {
      ".indexOn": "merchantId"
    },
    "merchants": {
      ".indexOn": "locations"
    },
    "locations-orders": {
      "$someid": {
        ".indexOn": ["orders/created_at"]
      }
    }
  }
}