Aside from the SERVER-6310 mentioned by Matt Johnson, one other workaround is to use the $project operator to add or subtract from the UTC time zone to “shift the time” into the correct local zone. Turns out you can add or subtract time in milliseconds. For example, assuming I have a Date field called orderTime. … Read more
You can insert a batch array of hashes using the ruby mongo driver’s insert method. From any Mongoid class, you can call collection to access it. batch = [{:name => “mongodb”}, {:name => “mongoid”}] Article.collection.insert(batch)
I expect it’s just a typo in the documentation. The _id field is primary key for every document. It’s called _id and is also accessible via id. Attempting to use an id key may result in a illegal ObjectId format error. That section is just indicating that the automatically generated ObjectIDs start with a timestamp … Read more
In MongoDB 2.6, the Aggregation Framework has a new array $size operator you can use: > db.mycollection.insert({‘foo’:[1,2,3,4]}) > db.mycollection.insert({‘foo’:[5,6,7]}) > db.mycollection.aggregate([{$project: { count: { $size:”$foo” }}}]) { “_id” : ObjectId(“5314b5c360477752b449eedf”), “count” : 4 } { “_id” : ObjectId(“5314b5c860477752b449eee0”), “count” : 3 }