我正在尝试转换看起来像这样的文档
{ "_id": 1,
"created_at": DateTimeObject,
"daily": [{ "impressions":13,
"clicks": 13,
"day": "2015-01-01" },
{ "impressions":15,
"clicks": 15,
"day": "2015-01-02" },
{ "impressions":20,
"clicks": 20,
"day": "2015-01-03" }]
}
到
{ "_id": 1,
"impressions": [["2015-01-01", 13],
["2015-01-02", 15],
["2015-01-03", 20]],
"clicks": [["2015-01-01", 13],
["2015-01-02", 15],
["2015-01-03", 20]] }
目前正在使用展开,我可以使用以下格式获取数据
{ "_id": 1,
"impressions": [{ "date": "2015-01-01", "value":13],
{"date":"2015-01-02", "value":15},
{"date":"2015-01-03", "value":20}],
"clicks": [{"date": "2015-01-01", "value":13},
{"date": "2015-01-01", "value":15},
{"date": "2015-01-01", "value":20}] }
我不想在数据库之外执行此操作,因为需要从类似文档生成大约150 - 200个折线图,并且更愿意进行转换。
编辑:这可以通过map reduce实现吗?
答案 0 :(得分:0)
Mongodb无法支持内部阵列。你需要用unwind和group编写。