将嵌套的BigQuery数据导出到云存储

Question

我正在尝试通过API将bigquery数据导出到Google云存储桶。我从这里https://cloud.google.com/bigquery/docs/exporting-
data
修改了代码段

Job job = table.extract(format, gcsUrl);
// Wait for the job to complete
try {
  Job completedJob = job.waitFor(WaitForOption.checkEvery(1, 
TimeUnit.SECONDS),
      WaitForOption.timeout(3, TimeUnit.MINUTES));
  if (completedJob != null && completedJob.getStatus().getError() == null) {
    // Job completed successfully
  } else {
    // Handle error case
       System.out.println(completedJob.getStatus().getError());
  }
} catch (InterruptedException | TimeoutException e) {
  // Handle interrupted wait

}

由于数据是嵌套的，因此无法与“ JSON”交换格式，因此无法将其与“
gs：//mybucket/export_*.json”导出为CSV和gcsUrl。但是错误消息告诉我以下问题：

transfer not working  BigQueryError{reason=invalid, location=null, message=Operation cannot be performed on a nested schema. Field: totals}

有什么建议怎么办？JSON应该能够处理嵌套格式…

Answer 1

谈到destinationFormat选项，你应该设置"NEWLINE_DELIMITED_JSON"为format以变量出口为JSON。