Question

我正在MongoDB中编写查询。我想对每条评论中的每个成绩进行计数，如果该成绩大于6，则增加Grades_Count和GradesMoreThan6_Count，如果不大于，则仅递增Grades_Count。我找不到可以在投影中使用的$ inc函数。我感谢所有帮助。

cancel_demand

评论数组

{$project: {
    _id: 1,
    reviews: 1,
    Grades_Count: NumberInt(0),
    GradesMoreThan6_Count: {$map:
                {input: "$reviews", as: "review", in: 
                    {$switch:
                    {branches:[
                        {case: { $gt: [ "$$review.responsive", 6 ] }},then: Grades_Count++ AND GradesMoreThan6_Count++},
                        {case: { $gt: [ "$$review.helpful", 6 ] }},then: Grades_Count++ AND GradesMoreThan6_Count++},
                        {case: { $gt: [ "$$review.kind", 6 ] }},then: Grades_Count++ AND GradesMoreThan6_Count++}
                      ],
                      default: Grades_Count++}}},

MongoDB如何在投影内部增加

0 个答案: