如何在Dataflow中使用BigQuery Standard SQL？

Question

我想在数据流中使用BigQuery Standard SQL运行一个简单的查询,但我找不到启用此选项的位置.我怎样才能做到这一点？

pipeline.apply(Read.named(metricName + " Read").fromQuery("select * from table1 UNION DISTINCT select * from table2"));

当我尝试运行它时,我收到错误:

2016-07-20T13:35:22.543Z: Error:   (6e0ad847af078af9): Workflow failed. Causes: (fe6c7bcb1a35a057): S01:warehouse_handled_returns Read/DataflowPipelineRunner.BatchBigQueryIONativeRead+ParMultiDo(FormatData)+warehouse_handled_returns Write/DataflowPipelineRunner.BatchBigQueryIOWrite/DataflowPipelineRunner.BatchBigQueryIONativeWrite failed., (7f29f1d9435d27bc): BigQuery execution failed., (7f29f1d9435d2823): Error:
Message: Encountered "" at line 23, column 27.

HTTP Code: 400

Answer 1

您现在可以将标准 SQL 与 Dataflow 结合使用。

https://cloud.google.com/dataflow/model/bigquery-io

PCollection<TableRow> weatherData = p.apply(
BigQueryIO.Read
.named("ReadYearAndTemp")
.fromQuery("SELECT year, mean_temp FROM `samples.weather_stations`")
.usingStandardSql();