我的集合包含具有以下架构的文档。我想过滤/查找所有包含女性性别的文档并汇总 Brainscore 的总和。我尝试了下面的语句，它显示了一个无效的管道错误。

db['!all'].aggregate({ $and: [ {'GENDER' :  'F'} , {'DOB' : { $gte : 19400801, $lte : 20131231 }} ]  }, { $group : { _id : "$GENDER", totalscore : { $sum : "$BRAINSCORE" } } } )

架构:

{
    "_id" : ObjectId("53f63fc8f2b643f6ebb8a1a9"),
    "DOB" : 19690112,
    "GENDER" : "F",
    "BRAINSCORE" : 65
},
{
    "_id" : ObjectId("53f63fc8f2b643f6ebb8a1a2"),
    "DOB" : 19950116,
    "GENDER" : "F",
    "BRAINSCORE" : 44
},
{
    "_id" : ObjectId("53f63fc8f2b643f6ebb8a902"),
    "DOB" : 19430216,
    "GENDER" : "M",
    "BRAINSCORE" : 71
}

最佳答案

您必须使用 $match :

db['!all'].aggregate([
  {$match:
    {'GENDER': 'F',
     'DOB':
      { $gte: 19400801,
        $lte: 20131231 } } },
  {$group:
     {_id: "$GENDER",
     totalscore:{ $sum: "$BRAINSCORE"}}}
])

输出:

{ "_id" : "F", "totalscore" : 109 }

https://stackoverflow.com/questions/25436630/