开发中有些按日期记录的记录需要各种维度的统计,按天,按月,按年,按小时,。。分组统计,还有些需要对字段去重统计,在之前的 [Mongo] 按时间分组统计(group时间格式化) 中用group实现了按天的统计,不过使用new Date()方法会有些坑,今天看了下aggreg
开发中有些按日期记录的记录需要各种维度的统计,按天,按月,按年,按小时,。。分组统计,还有些需要对字段去重统计,在之前的 [Mongo] 按时间分组统计(group时间格式化) 中用group实现了按天的统计,不过使用new Date()方法会有些坑,今天看了下aggregate中,使用聚合来写个时间统计。tips: aggregate 挺复杂,弄明白了再做笔记,现在只是根据需求来查询。
数据结构还是:
/* 0 */ { "_id" : ObjectId("541fcc51c6c36038bc6b81cd"), "url" : "http://wifi21.com/", "addtime" : ISODate("2014-08-19T00:15:02Z") } /* 1 */ { "_id" : ObjectId("541fcc51c6c36038bc6b81ce"), "url" : "http://meiwen.me/src/index.html", "addtime" : ISODate("2014-08-19T00:15:07Z") } ...按月统计pv值(相当于group)
db.msds_accessrecord.aggregate([ {$group: { _id: { "$month": "$addtime" }, pv: {$sum: 1}} }, {$sort: {"_id": 1}} ]);
统计结果
/* 0 */ { "result" : [ { "_id" : 8, "pv" : 583 }, { "_id" : 9, "pv" : 1399 } ], "ok" : 1 }
按月统计url值,重复url去掉,这里只是做个演示,可能统计没什么意义 (相当于group+distinct)
db.msds_accessrecord.aggregate([ {$group: { _id: { "month": {"$month": "$addtime"}, "url": "$url" } }}, {$group: {_id:"$_id.month", uv: {$sum: 1}}}, {$sort: {"_id":1}} ]);这里用到了管道,排序,聚合
统计结果
/* 0 */ { "result" : [ { "_id" : 8, "uv" : 41 }, { "_id" : 9, "uv" : 134 } ], "ok" : 1 }
引用:
聚合使用方法: http://docs.mongodb.org/manual/reference/method/db.collection.aggregate/#db.collection.aggregate
日期聚合函数: http://docs.mongodb.org/manual/reference/operator/aggregation-date/
本文出自 “orangleliu笔记本” 博客,请务必保留此出处http://blog.csdn.net/orangleliu/article/details/39932081

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