Tag Archives: mongoid

[mongoid] adding timestamps to an existing mongo collection

In our Rails 3 application we use mongo to store logging of critical actions. At first we did not store a separate timestamp, since the _id (which is a BSON::ObjectId contains a timestamp as well. Our model, simplified, looked like this: This is all fine and dandy, but when we wanted to build some reporting, […]

[mongoid] doing a group-by on date

Doing a simple group-by query using mongo and mongoid is actually pretty straightforward. According to the documentation, mongoid does not offer any group/aggregation function itself, but mongo does. And you can directly access the mongo using the collection. So assume we have a mongo collection: and now I want to count all occurrences of the […]