to_dot

# File activerecord/lib/arel/visitors/dot.rb, line 282
        def to_dot
          "digraph \"Arel\" {\nnode [width=0.375,height=0.25,shape=record];\n" +
            @nodes.map { |node|
              label = "<f0>#{node.name}"

              node.fields.each_with_index do |field, i|
                label += "|<f#{i + 1}>#{quote field}"
              end

              "#{node.id} [label=\"#{label}\"];"
            }.join("\n") + "\n" + @edges.map { |edge|
              "#{edge.from.id} -> #{edge.to.id} [label=\"#{edge.name}\"];"
            }.join("\n") + "\n}"
        end