【发布时间】:2013-06-26 02:06:58
【问题描述】:
数据库集合就像: “suid”:“8986691b1db3d99b6fbe27cceac2e19c”, “auid”:“22e7e5632acb4ac154b9bcb95710ca38”, “味精”:“ceshi1”, "ctime" : ISODate("2013-05-22T03:52:26.344Z"), “发送”:真的, “__v”:0, "_id" : ObjectId("519c411351db351236000001")
MongoDB shell 命令是: db.runCommand({"group":{ns:"messages",key:{"auid":true},"initial":{"lastmsgtime":0},condition:{auid:'456'},$reduce :function(doc,prev){senttime=doc.ctime.valueOf();if(senttime>prev.lastmsgtime){prev.suid=doc.suid;prev.lastmsgtime=new Date(senttime);}}, } } )
猫鼬可以做这个工作吗?
【问题讨论】: