Interval

Reads PostgreSQL's interval data type and transforms it into Rails' ActiveSupport::Duration. PostgreSQL Docs

How it works

Migration

Just set the type of the column as interval when creating a table.

create_table "courses" do |t|
  t.string   "title",    null: false
  t.interval "duration"
end

Or when you are adding or column, just use :interval as type.

add_column :courses, :duration, :interval

Using it

The column is automatically identified and the value is turned into ActiveSupport::Duration. So, any of the methods available on it can be used directly from your field. RubyOnRails Doc

# Shows when you'll be finishing the course
course.duration.from_now

The value can be set in different manners:

course.duration = 1.year                 # A new instance of ActiveSupport::Duration
course.duration = [1, 2, 3, 4, 5, 6]     # A list of values for the given order Y-M-D H:M:S
course.duration = [1, 0, 0]              # The list uses the right-most available positions, so this is H:M:S
course.duration = {days: 1, hours: 6}    # You can use complex hash notation
course.duration = 'P1Y2M3DT4H5M6S'       # It accepts ISO 8601 format, so form fields can cast to this type

course.duration = 259200
course.duration.parts.to_h == {days: 3}  # It also converts any set value to the correct separated duration