查询失败错误：在查询执行过程中超出资源：查询无法在分配的内存中执行

Question

我正在使用标准SQL。尽管它的基本查询仍然存在引发错误的问题。任何建议请

SELECT 
    fullVisitorId, 
    CONCAT(CAST(fullVisitorId AS string),CAST(visitId AS string)) AS session, 
    date, 
    visitStartTime, 
    hits.time, 
    hits.page.pagepath 
FROM 
    `XXXXXXXXXX.ga_sessions_*`, 
    UNNEST(hits) AS hits 
WHERE 
    _TABLE_SUFFIX BETWEEN "20160801" 
    AND "20170331" 
ORDER BY 
    fullVisitorId, 
    date, 
    visitStartTime 

Answer 1

此查询工作的唯一方法是通过去除最终应用的排序：

SELECT 
    fullVisitorId, 
    CONCAT(CAST(fullVisitorId AS string),CAST(visitId AS string)) AS session, 
    date, 
    visitStartTime, 
    hits.time, 
    hits.page.pagepath 
FROM 
    `XXXXXXXXXX.ga_sessions_*`, 
    UNNEST(hits) AS hits 
WHERE 
    _TABLE_SUFFIX BETWEEN "20160801" 
    AND "20170331" 

ORDER BY操作是相当昂贵的，并且不能被并行处理，从而尽量避免它（或尝试将其应用于有限的结果集中）

Answer 2

除了接受的答案，您可能希望按日期对表进行分区以减少使用昂贵查询的内存量。