First occasion experimenting with dates and times in MongoDB.
Currently, I have correctly inserted UTC dates into my documents:
{
"Value": 10
"DateTime": {
"$date": "2013-08-23T08:00:00.000Z"
},
}
I want to query the data to return all of the 'value' and datetime fields for all documents in which the hour is 08. I have gotten as far as:
db.readings.aggregate([{$project:{hour:{$hour:"$DateTime"}}},{$match:{hour:{"$in":[08]}}}])
Which returns the _id and "hour": 8 for all matching entries but I'm confused at how to proceed. It seems an unnecessarily complicated way to search and so I wonder if I am barking up the wrong tree here? Admittedly, I am somewhat out of my depth so some guidance would be appreciated.
You can try $expr expression operator to use aggregation operators ($hour) in query,
$expr to use aggregation operators$hour will return an hour from the date$eq to match hour and input hour 8db.collection.find({
$expr: {
$eq: [
{ $hour: "$DateTime" },
8
]
}
})