google-bigquery - 使用 TABLE_DATE_RANGE 展平

Question

我在数据集中有一系列表，需要在 FLATTENing 重复记录之一时查询所有表。例如，如下查询可以正常工作:

 SELECT
   date,
   customDimensions.value AS customDimension,
   hits.page.pagePath AS pagePath
FROM
   (FLATTEN( [<projectId>:<datasetId>.ga_sessions_20130910] ,
   customDimensions)) 
WHERE
   hits.page.pagePath CONTAINS '/helmets' 
   AND customDimensions.index IN (1,2,3)

但是，我在使用表通配符时遇到了 FLATTENing 问题。有人可以帮我解决语法吗？是否可以将 FLATTEN 与 TABLE_DATE_RANGE 一起使用？

SELECT
   date,
   customDimensions.value AS customDimension,
   hits.page.pagePath AS pagePath
FROM
   (FLATTEN (TABLE_DATE_RANGE ([<project>:<dataset>.ga_sessions_],
   TIMESTAMP('2013-09-10'),
   TIMESTAMP ('2014-06-10'))),
   customDimensions) 
WHERE
   hits.page.pagePath CONTAINS '/helmets' 
   AND customDimensions.index IN (1,2,3)

谢谢，
沙岩

Answer 1

根据引用手册，FLATTEN 语法是:

...(FLATTEN ([project_name:]datasetId.tableId, flattenField))..
...(FLATTEN (subselect_clause, flattenField))..

基于此，我会尝试在 FLATTEN 语句中放置一个子选择子句，如下所示:

SELECT
date,
customDimensions.value AS customDimension,
hits.page.pagePath AS pagePath
FROM
FLATTEN(
(SELECT date, customDimensions, hits FROM TABLE_DATE_RANGE ([<project>:<dataset>.ga_sessions_],
TIMESTAMP('2013-09-10'),TIMESTAMP ('2014-06-10')))
, customDimensions)
WHERE
hits.page.pagePath CONTAINS '/helmets' 
AND customDimensions.index IN (1,2,3)