我有以下收藏:
{
id: 23423-dsfsdf-32423,
name: Proj1,
services: [
{
id:sdfs-24423-sdf,
name:P1_Service1,
products:[{},{},{}]
},
{
id:sdfs-24jhh-sdf,
name:P1_Service2,
products:[{},{},{}]
},
{
id:sdfs-2jnbn3-sdf,
name:P1_Service3,
products:[{},{},{}]
}
]
},
{
id: 23423-cxcvx-32423,
name: Proj2,
services: [
{
id:sdfs-xvxcv-sdf,
name:P2_Service1,
products:[{},{},{}]
},
{
id:sdfs-xvwqw-sdf,
name:P2_Service2,
products:[{},{},{}]
},
{
id:sdfs-erdfd-sdf,
name:P2_Service3,
products:[{},{},{}]
}
]
}
我需要返回一个包含所有服务数组的文档:
{
services: [
{
id:sdfs-24423-sdf,
name:P1_Service1,
products:[{},{},{}]
},
{
id:sdfs-24jhh-sdf,
name:P1_Service2,
products:[{},{},{}]
},
{
id:sdfs-2jnbn3-sdf,
name:P1_Service3,
products:[{},{},{}]
},
{
id:sdfs-xvxcv-sdf,
name:P2_Service1,
products:[{},{},{}]
},
{
id:sdfs-xvwqw-sdf,
name:P2_Service2,
products:[{},{},{}]
},
{
id:sdfs-erdfd-sdf,
name:P2_Service3,
products:[{},{},{}]
}
]
}
我得到的最多是:
db.projects.aggregate({"$group":{"_id":"services","services":{"$push":"$services"}}})
但是这会返回一个包含数组数组的文档,我想要一个对象数组:
{
_id:"services",
services:[
[
{
id:sdfs-24423-sdf,
name:P1_Service1,
products:[{},{},{}]
},
{
id:sdfs-24jhh-sdf,
name:P1_Service2,
products:[{},{},{}]
},
{
id:sdfs-2jnbn3-sdf,
name:P1_Service3,
products:[{},{},{}]
}
],
[
{
id:sdfs-xvxcv-sdf,
name:P2_Service1,
products:[{},{},{}]
},
{
id:sdfs-xvwqw-sdf,
name:P2_Service2,
products:[{},{},{}]
},
{
id:sdfs-erdfd-sdf,
name:P2_Service3,
products:[{},{},{}]
}
]
]
}
我无法弄清楚数组聚合或连接或联合或其他什么。 最终我还必须为产品做同样的事情(将所有项目的所有服务的所有产品作为一个产品阵列并将文档返回到服务器但首先要做的事情......
10倍
答案 0 :(得分:3)
您需要对null
_id
进行分组,以便将所有services
分组到单个文档中。
同样在分组之前$unwind
服务数组,否则group将为您提供数组数组
db.project.aggregate(
{$unwind: '$services'},
{$group: {_id:null, services: {$push: '$services'}}}
)