Question

我正在尝试使用BigQuery中的虚拟表和数据来测试一些逻辑。我使用

成功完成了这项工作

WITH dummy AS (SELECT 1 AS a)
SELECT a FROM dummy

通过使用更复杂的WITH语句，我可以在这个虚拟表上尝试一些不同的逻辑。

现在我打了一堵墙，因为我在不同的分区中有一些我想要测试的数据。使用标准SQL我可以执行以下操作：

SELECT a
FROM
    `dummy_*`
WHERE
    _TABLE_SUFFIX BETWEEN '20161001' AND '20161003'

但是我真的希望能够为WITH子句中的子查询做同样的事情：

WITH 
    dummy_20161001 AS (SELECT 1 AS a UNION ALL SELECT 4 AS a),
    dummy_20161002 AS (SELECT 7 AS a UNION ALL SELECT 10 AS a)
SELECT a FROM dummy_*
WHERE
    _TABLE_SUFFIX BETWEEN '20161001' AND '20161003'

有什么东西我可以替换_TABLE_SUFFIX来执行此操作，还是有其他方法来创建表分区的虚拟表示形式？

Answer 1

在我看来，下面可以满足您的测试需求。至少这是一个选项：o）

WITH 
  dummy_20161001 AS (SELECT 1 AS a UNION ALL SELECT 2 AS a),
  dummy_20161002 AS (SELECT 3 AS a UNION ALL SELECT 4 AS a),
  dummy_20161003 AS (SELECT 5 AS a UNION ALL SELECT 6 AS a),
  dummy_20161004 AS (SELECT 7 AS a UNION ALL SELECT 8 AS a),
  `dummy_*` as (
    SELECT *, '20161001' as _TABLE_SUFFIX FROM dummy_20161001 UNION ALL
    SELECT *, '20161002' as _TABLE_SUFFIX FROM dummy_20161002 UNION ALL
    SELECT *, '20161003' as _TABLE_SUFFIX FROM dummy_20161003 UNION ALL
    SELECT *, '20161004' as _TABLE_SUFFIX FROM dummy_20161004
  )
SELECT a 
FROM `dummy_*`
WHERE
    _TABLE_SUFFIX BETWEEN '20161001' AND '20161003'

Answer 2

_TABLE_SUFFIX和（如果使用分区表 - _PARTITIONTIME）伪列仅适用于BigQuery托管表。

您是否可以将示例数据写入多个表或单个分区表（使用带有destination_table的SELECT查询）？之后，您应该能够使用伪列。

子查询上的通配符

2 个答案: