MongoDB comparing dates only without times

Question

How do I query for a date field in MongoDB with the date only, and not times? For example, if MongoDB stores July 7, 2015 with any time, I want to match that day only with today's date.

In MySQL, I would do SELECT col1, col2 FROM table WHERE DATE(date_field) = DATE(NOW());

Notice how MySQL has a function to change the date_field to the date only during matching. Can I do this in MongoDB with a similar function during matching? Like Collection.find({ dateonly(datetimefield): dateonly(new Date() }); or something of the like?

I understand Mongo stores date/times in GMT, so I would also have to convert the stored GMT date+time from GMT to Local before matching the date only, but to get me started, would like to know if I can strip the time off of a date match. For example, if GMT now is July 8 at 03:00 but Local Eastern Time US is July 7 at 23:00 then I would want to match July 7.

Answer 1

I guess You should make a range query between the start of the day and its ending(or without ending if you are talking about today). Something like this

db.collection.find({   "date" : {"$gte": new Date("2015-07-07T00:00:00.000Z"),             "$lt": new Date("2015-07-08T00:00:00.000Z")} }) 

Answer 2

You can extract the date as string at any given format and compare it with your date at that format using aggregation pipiline

$addFields: { "creationDate":  {$dateToString:{format: "%Y-%m-%d", date: "$createdAt"}}}}, {$match :  { creationDate:  {$eq: req.query.date}}