search serialize object with pgsql with rails3

My object is this

<Product id: 44, data: {:my_data=>{"1"=>"5", "2"=>"test", "3"=>"tes"}}, view_cout: 1>

Want to create filter on the basic of my_data I got to know two ways first I can create separate table for it and second is hstore . But in both the ways I have to change my existing logic and form so is there any other way by which I need not to modify lots of thing as I do have lots of record on this thanks.