I am new to ruby and I want to know how can I define a variable whose
scope is restricted to a particular controller.
What I am trying to achieve is this - based on the parameters
specified by user, I make some queries to database. The results of the
query are consumed by different methods in that controller. What I
want to achieve is - I want to make all the queries before the page
loads and store them in some variable and I want to access these
variables across different methods in the controller.