Using Active Record generators after Mongoid installation?
rails g active_record:migration
mongoid
Difference between “id” and “_id” fields in MongoDB
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
Mongoid or MongoMapper? [closed]
I have used MongoMapper for awhile but decided to migrate to MongoId. The reason is hidden issues plus arrogance towards users. I had to jump through hoops to make MongoMapper work with Cucumber (succeeded in the end) and to put a couple of patches even the project was simple, but it’s not the point. When … Read more
Select where not null or empty in mongoid
Try Model.where(:url.ne => “”, :url.exists => true).count see Mongoid Symbol Operators
How to implement has_many :through relationships with Mongoid and mongodb?
Mongoid doesn’t have has_many :through or an equivalent feature. It would not be so useful with MongoDB because it does not support join queries so even if you could reference a related collection via another it would still require multiple queries. https://github.com/mongoid/mongoid/issues/544 Normally if you have a many-many relationship in a RDBMS you would model … Read more