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Giving ActiveRecord finders an :offset but not a :limit

Sometimes you might want to find all records from a specific offset but ActiveRecord won’t let you: if you use the :offset option without specifying a :limit you won’t get an error, Rails will just silently discard the offset.

You could get around this by passing :limit => MyModel.count option to the finder but this adds the unnecessary overhead of an additional query. Instead I prefer to pass a value that is more than the largest possible value for the primary key, like this:

MyModel.all :offset => 100, :limit => 2**32, :order => :name

In this example MyModel has a regular integer sized primary key so 2**32 is larger than the maximum number of records that can be stored in the table, so we’re guaranteed to get all the records from offset 100 onwards.