我在我的数据库中有这些数据集:
[{
"id": 1,
"date": "2019/11/30",
"title": "Data Title",
"tags": ["Javascript", "NodeJS", "Big Data", "MongoDB"],
},{
"id": 2,
"date": "2019/10/30",
"title": "Data Title 2",
"tags": ["Javascript", "React", "NodeJS", "Postgres"],
}]
目前我想做的是按标签分组数据,并返回类似于以下内容的值:
[{
"id": 1,
"tags": "Javascript",
"data": [{
"date": "2019/11/30",
"title": "Data Title",
},{
"date": "2019/10/30",
"title": "Data Title 2",
}],
"count": 2
}, {
"id": 2,
"tags": "React",
"data": [{
"date": "2019/10/30",
"title": "Data Title 2",
}],
"count": 1
}]
问题:如何使用MongoDB聚合查询获取数据?非常感谢!