Because t.string :string is used in the ActiveAdmin Settings migrations, long strings (or settings of type text) are truncated at 255 in MySQL.
The solution is to revise the migration to be the following:
# This migration comes from activeadmin_settings (originally 20121123145237)
class CreateActiveadminSettingsSettings < ActiveRecord::Migration
def change
create_table :activeadmin_settings_settings do |t|
t.string :name
t.text :string
t.string :file
t.timestamps
end
end
end
By using t.text it should allow any length, I believe.