Validates Lengths from Database
Few people add length validations to fields in their database, and when saving such fields that have exhausted their length, an SQL error occurs. This gem introspects your table schema for maximum lengths on string and text fields and automatically adds length validations to the model.
Include the gem using bundler in your Gemfile:
In your model you can activate validations:
class Post < ActiveRecord::Base validates_lengths_from_database end
It also supports filter-style :only and :except options:
class Post < ActiveRecord::Base validates_lengths_from_database :only => [:title, :contents] end class Post < ActiveRecord::Base validates_lengths_from_database :except => [:other_field] end
Note that this cannot be done at a global level directly against ActiveRecord::Base, since the validates_length_from_database method requires the class to have a table name (with the ability to load the schema).