Function DeclarationToSchema

cpp/src/arrow/acero/exec_plan.cc:627–643

}  // namespace

Result<std::shared_ptr<Schema>> DeclarationToSchema(const Declaration& declaration,
                                                    FunctionRegistry* function_registry) {
  // We pass in the default memory pool and the CPU executor but nothing we are doing
  // should be starting new thread tasks or making large allocations.
  ExecContext exec_context(default_memory_pool(), ::arrow::internal::GetCpuThreadPool(),
                           function_registry);
  ARROW_ASSIGN_OR_RAISE(std::shared_ptr<ExecPlan> exec_plan,
                        ExecPlan::Make(exec_context));
  ARROW_ASSIGN_OR_RAISE(ExecNode * last_node, declaration.AddToPlan(exec_plan.get()));
  ARROW_ASSIGN_OR_RAISE(last_node, EnsureSink(last_node, exec_plan.get()));
  ARROW_RETURN_NOT_OK(exec_plan->Validate());
  if (last_node->inputs().size() != 1) {
    // Every sink node today has exactly one input
    return Status::Invalid("Unexpected sink node with more than one input");
  }
  return last_node->inputs()[0]->output_schema();
}

namespace {