分类：mongodb聚合操作

2021
04-09

MongoDB聚合group的操作指南

MongoDB聚合MongoDB中聚合(aggregate)主要用于处理数据(诸如统计平均值,求和等)，并返回计算后的数据结果。有点类似sql语句中的count(*)。基本语法为：db.collection.aggregate([<stage1>,<stage2>,...])现在在mycol集合中有以下数据：{"_id":1,"name":"tom","sex":"男","score":100,"age":34}{"_id":2,"name":"jeke","sex":"男","score":90,"age":24}{"_id":3,"name":"kite","sex... 继续阅读 >