我正在阅读Mongodb有关聚合框架和MapReduce的文档,但仍然不知道如何开始对整数数组的“列”进行聚合。例如,考虑以下文档:
[{ "_id" : "A", "agent" : "006", "score" : [ 1, 0, 0 ], "qv" : [ 1, 0, 1, 0, 1 ] },
{ "_id" : "B", "agent" : "006", "score" : [ 0, 1, 0 ], "qv" : [ 1, 0, 1, 0, 1 ] },
{ "_id" : "C", "agent" : "006", "score" : [ 1, 0, 0 ], "qv" : [ 1, 0, 1, 0, 0 ] },
{ "_id" : "D", "agent" : "007", "score" : [ 1, 0, 0 ], "qv" : [ 1, 0, 1, 0, 0 ] }]
预期结果应该如下所示:
[
{"agent": "006", "score": [2, 1, 0], "qv": [3, 0, 3, 0, 2]},
{"agent": "007", "score": [1, 0, 0], "qv": [1, 0, 1, 0, 0]}
]
聚合框架足以完成这个任务,还是应该使用Mapreduce?