First off, this actually is being raised in the next version to 8MB or 16MB … but I think to put this into perspective, Eliot from 10gen (who developed MongoDB) puts it best: EDIT: The size has been officially ‘raised’ to 16MB So, on your blog example, 4MB is actually a whole lot.. For example, … Read more
BSON is the binary encoding of JSON-like documents that MongoDB uses when storing documents in collections. It adds support for data types like Date and binary that aren’t supported in JSON. In practice, you don’t have to know much about BSON when working with MongoDB, you just need to use the native types of your … Read more
Although $date is a part of MongoDB Extended JSON and that’s what you get as default with mongoexport, I don’t think you can really use it as a part of the query. If try exact search with $date like below: db.foo.find({dt: {“$date”: “2012-01-01T15:00:00.000Z”}}) you’ll get the error: error: { “$err” : “invalid operator: $date”, “code” … Read more
db.messages.find( { headers : { From: “reservations@marriott.com” } } ) This queries for documents where headers equals { From: … }, i.e. contains no other fields. db.messages.find( { ‘headers.From’: “reservations@marriott.com” } ) This only looks at the headers.From field, not affected by other fields contained in, or missing from, headers. Dot-notation docs