mongodb:按条件获取嵌套数组的元素
需要按条件获取嵌套数组的元素。产地来源:mongodb:按条件获取嵌套数组的元素,mongodb,aggregation-framework,Mongodb,Aggregation Framework,需要按条件获取嵌套数组的元素。产地来源: [ { code: 134, bindings: [ { devId: "71156ce8-ac2b-4282-9f5a-10133441057c", userIds: ["9d300b89-29c0-45a8-a4d3-019cfc8f1c7b"] }, { devId: "ca33efa1-ec27-4ee1-8117-8b8ab29c1790",
[
{
code: 134,
bindings: [
{
devId: "71156ce8-ac2b-4282-9f5a-10133441057c",
userIds: ["9d300b89-29c0-45a8-a4d3-019cfc8f1c7b"]
},
{
devId: "ca33efa1-ec27-4ee1-8117-8b8ab29c1790",
userIds: ["73e5af2f-fe01-41a3-bebd-6bab895cab58"]
},
{
devId: "a03f5fbd-f279-4182-bfb6-33aba9de5751",
userIds: ["dc0c5e59-ef1a-44b9-843b-a4ea73bbed2e"]
}
]
}
]
我尝试使用聚合函数:
db.trigger.aggregate([
{ $match: { _id: "134" } },
{ $unwind: "$bindings" },
{ $match: { "bindings.devId": "ca33efa1-ec27-4ee1-8117-8b8ab29c1790" } },
{ $project: { _id: 0, dateset: 1 } },
{ $out: "bindings" }
]);
但它并没有给出预期的结果。С有人告诉我我做错了什么吗?您可以尝试以下聚合,将嵌套文档提升到根级别:
db.collection.aggregate([
{
$match: { code: 134 }
},
{
$unwind: "$bindings"
},
{
$match: { "bindings.devId": "71156ce8-ac2b-4282-9f5a-10133441057c" }
},
{
$replaceRoot: { newRoot: "$bindings" }
}
])
示例文档的
code
设置为134
,而在查询中,您试图匹配的id是一个字符串。你能给我们看一下想要的结果吗?想要的结果:{devId:“71156ce8-ac2b-4282-9f5a-10133441057c”,用户ID:[“9d300b89-29c0-45a8-a4d3-019cfc8f1c7b”]}具有特定设备名称的数组元素。谢谢!