Can I query MongoDB ObjectId by date?
In pymongo
, it can be done this way:
import datetime
from bson.objectid import ObjectId
mins = 15
gen_time = datetime.datetime.today() - datetime.timedelta(mins=mins)
dummy_id = ObjectId.from_datetime(gen_time)
result = list(db.coll.find({"_id": {"$gte": dummy_id}}))
Using inbuilt function provided by mongodb drivers in in Node.js lets you query by any timestamp:
var timestamp = Date.now();
var objectId = ObjectID.createFromTime(timestamp / 1000);
Alternatively, to search for records before the current time, you can simply do:
var objectId = new ObjectID(); // or ObjectId in the mongo shell
Source: http://mongodb.github.io/node-mongodb-native/api-bson-generated/objectid.html
Popping Timestamps into ObjectIds covers queries based on dates embedded in the ObjectId in great detail.
Briefly in JavaScript code:
/* This function returns an ObjectId embedded with a given datetime */
/* Accepts both Date object and string input */
function objectIdWithTimestamp(timestamp) {
/* Convert string date to Date object (otherwise assume timestamp is a date) */
if (typeof(timestamp) == 'string') {
timestamp = new Date(timestamp);
}
/* Convert date object to hex seconds since Unix epoch */
var hexSeconds = Math.floor(timestamp/1000).toString(16);
/* Create an ObjectId with that hex timestamp */
var constructedObjectId = ObjectId(hexSeconds + "0000000000000000");
return constructedObjectId
}
/* Find all documents created after midnight on May 25th, 1980 */
db.mycollection.find({ _id: { $gt: objectIdWithTimestamp('1980/05/25') } });