Method Flush

cpp/src/arrow/table_builder.cc:53–87

}

Result<std::shared_ptr<RecordBatch>> RecordBatchBuilder::Flush(bool reset_builders) {
  std::vector<std::shared_ptr<Array>> fields;
  fields.resize(this->num_fields());

  int64_t length = 0;
  for (int i = 0; i < this->num_fields(); ++i) {
    RETURN_NOT_OK(raw_field_builders_[i]->Finish(&fields[i]));
    if (i > 0 && fields[i]->length() != length) {
      return Status::Invalid("All fields must be same length when calling Flush");
    }
    length = fields[i]->length();
  }

  // For certain types like dictionaries, types may not be fully
  // determined before we have flushed. Make sure that the RecordBatch
  // gets the correct types in schema.
  // See: #ARROW-9969
  std::vector<std::shared_ptr<Field>> schema_fields(schema_->fields());
  for (int i = 0; i < this->num_fields(); ++i) {
    if (!schema_fields[i]->type()->Equals(fields[i]->type())) {
      schema_fields[i] = schema_fields[i]->WithType(fields[i]->type());
    }
  }
  std::shared_ptr<Schema> schema =
      std::make_shared<Schema>(std::move(schema_fields), schema_->metadata());

  std::shared_ptr<RecordBatch> batch =
      RecordBatch::Make(std::move(schema), length, std::move(fields));

  if (reset_builders) {
    ARROW_RETURN_NOT_OK(InitBuilders());
  }

  return batch;
}

Result<std::shared_ptr<RecordBatch>> RecordBatchBuilder::Flush() { return Flush(true); }