Remove old records in mongodb based on Month

Question

I am trying to delete Older records present in my collection .

I have a collection named "user_track" , which consists of data in this format shown below

db.user_track.find().pretty()
{
        "_id" : ObjectId("50c9afe5765fb0e4fea076ce"),
        "cust_id" : "ddddd",
        "symbol" : "WWWW",
        "access_time" : "Thu Dec 13 2012 05:37:25 GMT-0500 (EST)"
}
{
        "_id" : ObjectId("50c9afe7765fb0e4ffa076ce"),
        "cust_id" : "eeeeeeeeee",
        "symbol" : "WFC",
        "access_time" : "Thu Dec 13 2012 05:37:27 GMT-0500 (EST)"
}
{
        "_id" : ObjectId("522de3ae2191b0e41a7534dd"),
        "cust_id" : "dsdsds",
        "symbol" : "APPLE",
        "access_time" : "Mon Sep 09 2013 11:05:18 GMT-0400 (EDT)"
}

In my collection , user_track , i want to keep only the current month's data (that is from Sep 01 2013 to current day ) and want to delete the rest of the records which doesn't belong to current month

I have tried to issue the below command , but i am not sure of how to issue this command to suit my requirement as the date i have is in different format .

db.user_track.delete( { 'access_time': {$lte: XXX} })

Please suggest .

Answer 1

You can give any Date with Javascript date

db.user_track.remove( { access_time : {"$lt" : new Date(year, month_0_indexed, day)} })

So for removing documents before 1 September 2013 your command should be

db.user_track.remove( { access_time : {"$lt" : new Date(2013, 8, 1) } })

September is the 9th month but the month field is zero indexed. So we make that as 8.

Answer 2

Mongo has a TTL feature on collections, I think this is a nice solution to such cases:

https://docs.mongodb.com/manual/tutorial/expire-data/

Basically something like:

db.log_events.createIndex( { "createdAt": 1 }, { expireAfterSeconds: 3600 } )