mongodb复杂语句操作

db.r0audio.find().forEach(function(item){
db.r0audio.update({"_id":item._id},
{"$set": {"day":item.fileCreateTime.substring(0,8)}},false,true)
});

# function语法为js，实现更新一个字段的值为另外一个字段的值

db.r0audio.aggregate([
  { $match: {"fileInfoPushTime":{$gte:"202305190000"}}},
    {$group:{"_id":{$substr:['$fileInfoPushTime',0,8]}, count:{$sum:1}}}
]);

# mongo截取字符串后group by count

db.r0audio.aggregate(
    {"$match":{"pid":{"$in":["914013694","914013669","914013668","914013628","914013588"]},"fileInfoPushTime":{$gte:"20230101000000"}}},
    {
        "$group": {
            "_id": "$pid",
            "count": {
                "$sum": "$duration"
            }
        }
    }
)
# 分组查询聚合统计