Ruby On Rails Active Record data format type :primary_key, :string, :text, :integer, :float, :decimal, :datetime, :timestamp, :time, :date, :binary, :boolean.

The types supported by Active Record are  
:primary_key,
:string,  
:text,  
:integer,  
:float,  
:decimal,  
:datetime,  
:timestamp,
:time,  
:date,  
:binary,  
:boolean

jz another helpful reference for a newbie like me ~.~