Question

我正在尝试首先在group.name上对'group.name'填充“角色”文档，然后在role.name

上

return this.find(query, { _group: 1, name: 1, _id:0 } )
  .populate('_group', 'name -_id')
  .sort({ '_group.name': 1, name: 1 })

但它没有按预期工作，我只在role.name

上排序

ROLES:[
{"name":"NewRole"},
{"name":"NewRoleInGroup","_group":{"name":"GroupA"}},
{"_group":{"name":"GroupA"},"name":"admin"},
{"_group":{"name":"GroupA"},"name":"employee"},
{"_group":{"name":"GroupB"},"name":"employee"},
{"_group":{"name":"GroupC"},"name":"employee"},
{"_group":{"name":"GroupA"},"name":"manager"},
{"_group":{"name":"GroupB"},"name":"manager"},
{"name":"visitor"}
]

我想宁愿：

ROLES:[
// NO GROUP
{"name":"NewRole"},
{"name":"visitor"}.
// GroupA
{"_group":{"name":"GroupA"},"name":"admin"},
{"_group":{"name":"GroupA"},"name":"employee"},
{"_group":{"name":"GroupA"},"name":"manager"},
{"name":"NewRoleInGroup","_group":{"name":"GroupA"}},
// GroupB
{"_group":{"name":"GroupB"},"name":"employee"},
{"_group":{"name":"GroupB"},"name":"manager"},
// GroupC
{"_group":{"name":"GroupC"},"name":"employee"}
]

感谢您的反馈

UPDATE 根据@Talha评论：

使用聚合，我接近我需要的东西...但是，我得到一个数组内的组数据，在多对一关系中，在这种情况下只有一个组...如何投影group作为数组中的第一个对象：“group”：{}或“group”：{“name”; ......，“描述”：......}？

  return this.aggregate([
    { $match: query},
    {
      $lookup: {
        from: 'groups',
        localField: '_group',
        foreignField: '_id',
        as: 'group'
      }
    }
    ,
    {
      $project: {
        'group.name': 1,
        'group.description': 1,
        name: 1,
        description: 1,
        _id: 0
      }
    },
    { $sort: { 'name': 1 } },
    { $limit: limit },
    { $skip: skip }
  ])


 ROLES: [
// NO GROUP
{"name":"NewRole","description":"NewRole description","group":[]},
{"name":"Visitor","description":"no permissions","group":[]},
// GROUP A
{"name":"NewRoleInGroup","description":"NewRoleInGroup description","group":[{"name":"GroupA","description":"Description GroupA"}]},
{"name":"admin","description":"can RW group, user","group":[{"name":"GroupA","description":"Description GroupA"}]},
{"name":"employee","description":"can R group, can read user","group":[{"name":"GroupA","description":"Description GroupA"}]},
{"name":"manager","description":"can R group, can RW user","group":[{"name":"GroupA","description":"Description GroupA"}]},
// GROUP B
{"name":"employee","description":"can R group, can read user","group":[{"name":"GroupB","description":"Description GroupB"}]},
{"name":"manager","description":"can R group, can RW user","group":[{"name":"GroupB","description":"Description GroupB"}]},
// GROUP C
{"name":"employee","description":"can R group, can read user","group":[{"name":"GroupC","description":"Description GroupC"}]}]

Answer 1

我应该使用以下函数w aggregate：

  return this.aggregate([
    { $match: query},
    {
      $lookup: {
        from: 'groups',
        localField: '_group',
        foreignField: '_id',
        as: 'group'
      }
    },
    {
      $project: {
        group: {
          $let:{
            vars:{
              firstGroup:{
                $arrayElemAt:["$group",0]
              }
            },
            in:{
              name:"$$firstGroup.name",
              description:"$$firstGroup.description"
            }
          }
        },
        name: 1,
        description: 1,
        _id: 0
      }
    },
    { $sort: { 'group.name': 1, 'name': 1 } },
    { $limit: limit },
    { $skip: skip }
  ])
  .exec()
  .then((list) => {
    return list;
  })

这将输出正确排序的列表（1 / by group.name 2 / ny role.name），并将该组输出到查找输出数组中：

ROLES: [
// NO GROUP
{"name":"NewRole","description":"NewRole description","group":{}},
{"name":"Visitor","description":"no permissions","group":{}},
// GROUP A
{"name":"NewRoleInGroup","description":"NewRoleInGroup description","group":{"name":"GroupA","description":"Description GroupA"}},
{"name":"admin","description":"can RW group, user","group":{"name":"GroupA","description":"Description GroupA"}},
{"name":"employee","description":"can R group, can read user","group":{"name":"GroupA","description":"Description GroupA"}},
{"name":"manager","description":"can R group, can RW user","group":{"name":"GroupA","description":"Description GroupA"}},
// GROUP B
{"name":"employee","description":"can R group, can read user","group":{"name":"GroupB","description":"Description GroupB"}},
{"name":"manager","description":"can R group, can RW user","group":{"name":"GroupB","description":"Description GroupB"}},
// GROUP C
{"name":"employee","description":"can R group, can read user","group":{"name":"GroupC","description":"Description GroupC"}}]

mongoose-如何对多标准w群体进行排序

1 个答案: