ruby-on-railsrubyactiverecordrails-activerecordactive-relation

Difference between ActiveRecord and ActiveRecord::Relation objects

I have searched but not able to find the brief explanation for the difference between ActiveRecord and ActiveRecord::relation object.

I have understand that ActiveRecord is the single object find by something like

User.find(1)

And ActiveRecord::Relation is the array like object Find by something like

User.where(id: 1)

I am looking for the difference between them in terms of query execution or deep explanation about them, so it will clear the whole concept behind it.

Thanks in advance!

Solution

  • An instance of ActiveRecord::Base is an object that represents a specific row of your database (or might be saved into the database).

    Whereas, an instance of ActiveRecord::Relation is a representation of a query that can be run against your database (but wasn't run yet). Once you run that query by calling to_a, each, first etc. on that Relation a single instance or an array of ActiveRecord::Base instances will be returned.