I am trying to run a map/reduce function in mongodb where I group by 3 different fields contained in objects in my collection. I can get the map/reduce function to run, but all the emitted fields run together in the output collection. I m not sure this is normal or not, but outputting the data for analysis takes more work to clean up. Is there a way to separate them, then use mongoexport?
让我向你表明,我指的是:
我试图按日、用户识别(或设计)和目的地分类的田地。
我行使这些职能:
map = function() {
day = (this.created_at.getFullYear() + "-" + (this.created_at.getMonth()+1) + "-" + this.created_at.getDate());
emit({day: day, uid: this.uid, destination: this.destination}, {count:1});
}
/* Reduce Function */
reduce = function(key, values) {
var count = 0;
values.forEach(function(v) {
count += v[ count ];
}
);
return {count: count};
}
/* Output Function */
db.events.mapReduce(map, reduce, {query: {destination: {$ne:null}}, out: "TMP"});
产出如下:
{ "_id" : { "day" : "2012-4-9", "uid" : "1234456", "destination" : "Home" }, "value" : { "count" : 1 } }
{ "_id" : { "day" : "2012-4-9", "uid" : "2345678", "destination" : "Home" }, "value" : { "count" : 1 } }
{ "_id" : { "day" : "2012-4-9", "uid" : "3456789", "destination" : "Login" }, "value" : { "count" : 1 } }
{ "_id" : { "day" : "2012-4-9", "uid" : "4567890", "destination" : "Contact" }, "value" : { "count" : 1 } }
{ "_id" : { "day" : "2012-4-9", "uid" : "5678901", "destination" : "Help" }, "value" : { "count" : 1 } }
当我尝试使用<代码>mongo Export<>/code>时,由于地图将田地结合起来,我无法按栏目分开一天、构造或目的地。
我希望:
{ { "day" : "2012-4-9" }, { "uid" : "1234456" }, { "destination" : "Home"}, { "count" : 1 } }
Is this even possible?
除此以外,我通过在档案中应用<条码>和<条码>来完成产出工作,并清理了《社会保障法》。 更多工作,但其工作。 如果我能以正确格式从<代码>mongodb中删除,那将是理想的。