title: How can I use mongodump to dump out records matching a specific date range?
body: <p>I'm trying to use the mongodump command to dump out a bunch of records created on a specific date. The records include a "ts" field which is a MongoDB Date() object.</p>
  
  <p>mongodump takes a -q argument which can be used to run a query to select the records to be included in the dump. Unfortunately, the -q argument needs to be provided in JSON, and it's not clear how to express a "less-than-this-date, more-than-this-date" query in pure JSON (normally such queries would use a 'new Date()' constructor)"</p>
  
  <p>Any tips? I've tried using the {$date: unix-timestamp-in-milliseconds} format but it's not working for me.</p>