ResultSet
result variable: a
size: 4
solution: ResultSolution
  binding: ResultBinding
    variable: a
    value: v-2-1
solution: ResultSolution
  binding: ResultBinding
    variable: a
    value: v-1-2
solution: ResultSolution
  binding: ResultBinding
    variable: a
    value: v-1-1
solution: ResultSolution
  binding: ResultBinding
    variable: a
    value: v-2-2