How to check if a model has a certain column/attribute?

For a class

Use Class.column_names.include? attr_name where attr_name is the string name of your attribute.

In this case: Number.column_names.include? 'one'

For an instance

Use record.has_attribute?(:attr_name) or record.has_attribute?('attr_name') (Rails 3.2+) or record.attributes.has_key? attr_name.

In this case: number.has_attribute?(:one) or number.has_attribute?('one') or number.attributes.has_key? 'one'