比如集合里有个字段保存的是时间戳类型,那么在转换成日期的时候,默认为UTC时间,这里需要转换:
方案1:
db.coll_name.aggregate([
{"$match":{"_id":ObjectId("61c99e5eecd50125e15d79a6")}},
{
"$group":{
"_id":{
"beginDate":{
"$dateToString":{
"date":{
"$add":[new Date(0),"$beginTime"]
},
"format":"%Y-%m-%d %H:%M",
"timezone":"Asia/Shanghai"
}
}
},
"total":{"$sum":1}
}
}
]);
方案2:需要加上8小时对应的毫秒数
db.tb_veh_run_abnormal.aggregate([
{"$match":{"_id":ObjectId("61c99e5eecd50125e15d79a6")}},
{
"$group":{
"_id":{
"beginDate":{
"$dateToString":{
"date":{
"$add":[new Date(0),"$beginTime",28800000]
},
"format":"%Y-%m-%d %H:%M"
}
}
},
"total":{"$sum":1}
}
}
]);
其他:字符串到日期的转换
db.foo.aggregate([
{ $match: { _id: 1 } },
{ $project: {
utc: { $dateFromString: { dateString: '$bar', timezone: "UTC" } },
honolulu: { $dateFromString: { dateString: '$bar', timezone: "Pacific/Honolulu" } },
auckland: { $dateFromString: { dateString: '$bar', timezone: "Pacific/Auckland" } } } }
])