Javascript 如何使用组过滤mongo db中的数据？
我正在尝试使用Javascript 如何使用组过滤mongo db中的数据？,javascript,node.js,mongodb,mongoose,mongodb-query,Javascript,Node.js,Mongodb,Mongoose,Mongodb Query,我正在尝试使用$group对数据进行分组，但未获得预期的输出。 这是我的密码 获取输出 [ { "_id": { "empid": "a2" }, "data": [ { "attendence": "P", "date": "2019-07-02T00:00:00.000Z", "id": "e
$group[
{
"_id": {
"empid": "a2"
},
"data": [
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "ec8d2107f1ec9c509845232f5aeeadd4"
},
{
"attendence": "A",
"date": "2019-07-01T00:00:00.000Z",
"id": "c91a157c038328d0a9a9d501b2322ee4"
}
]
},
{
"_id": {
"empid": "a1"
},
"data": [
{
"attendence": "A",
"date": "2019-07-03T00:00:00.000Z",
"id": "e85904145b5c104f108a701ab4a7d511"
},
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "75f8f4bd1db70519d90e740a89d5b77d"
},
{
"attendence": "P",
"date": "2019-07-01T00:00:00.000Z",
"id": "a1e428379285f56c021f4792e74ed520"
}
]
}
]
[
{
"empid": "a2",
"name": "rajat",
"data": [
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "ec8d2107f1ec9c509845232f5aeeadd4"
},
{
"attendence": "A",
"date": "2019-07-01T00:00:00.000Z",
"id": "c91a157c038328d0a9a9d501b2322ee4"
}
]
},
{
"empid": "a1",
name:"ravi",
"data": [
{
"attendence": "A",
"date": "2019-07-03T00:00:00.000Z",
"id": "e85904145b5c104f108a701ab4a7d511"
},
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "75f8f4bd1db70519d90e740a89d5b77d"
},
{
"attendence": "P",
"date": "2019-07-01T00:00:00.000Z",
"id": "a1e428379285f56c021f4792e74ed520"
}
]
}
]
[
{
"_id": {
"empid": "a2"
},
"data": [
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "ec8d2107f1ec9c509845232f5aeeadd4"
},
{
"attendence": "A",
"date": "2019-07-01T00:00:00.000Z",
"id": "c91a157c038328d0a9a9d501b2322ee4"
}
]
},
{
"_id": {
"empid": "a1"
},
"data": [
{
"attendence": "A",
"date": "2019-07-03T00:00:00.000Z",
"id": "e85904145b5c104f108a701ab4a7d511"
},
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "75f8f4bd1db70519d90e740a89d5b77d"
},
{
"attendence": "P",
"date": "2019-07-01T00:00:00.000Z",
"id": "a1e428379285f56c021f4792e74ed520"
}
]
}
]
[
{
"empid": "a2",
"name": "rajat",
"data": [
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "ec8d2107f1ec9c509845232f5aeeadd4"
},
{
"attendence": "A",
"date": "2019-07-01T00:00:00.000Z",
"id": "c91a157c038328d0a9a9d501b2322ee4"
}
]
},
{
"empid": "a1",
name:"ravi",
"data": [
{
"attendence": "A",
"date": "2019-07-03T00:00:00.000Z",
"id": "e85904145b5c104f108a701ab4a7d511"
},
{
"attendence": "P",
"date": "2019-07-02T00:00:00.000Z",
"id": "75f8f4bd1db70519d90e740a89d5b77d"
},
{
"attendence": "P",
"date": "2019-07-01T00:00:00.000Z",
"id": "a1e428379285f56c021f4792e74ed520"
}
]
}
]