ResultSet
result variable: y
result variable: a
result variable: b
result variable: x
result variable: z
size: 2
solution: ResultSolution
  binding: ResultBinding
    variable: y
    value: r2
  binding: ResultBinding
    variable: a
    value: r1
  binding: ResultBinding
    variable: b
    value: r-2-1
  binding: ResultBinding
    variable: x
    value: r1
  binding: ResultBinding
    variable: z
    value: r-1-2
solution: ResultSolution
  binding: ResultBinding
    variable: y
    value: r1
  binding: ResultBinding
    variable: a
    value: r2
  binding: ResultBinding
    variable: b
    value: r-1-2
  binding: ResultBinding
    variable: x
    value: r2
  binding: ResultBinding
    variable: z
    value: r-2-1