SQL嵌套数据运行总计，直到达到值为止

我试图使用以下教程在Google BigQuery上使用复杂的嵌套数据集：

导出为json的数据如下所示：

我正在使用的有效示例是：

但是，我希望在SUMbin.density达到0.7时输出bin.end值time。我的预期输出如下所示：

1   4G  1000     
2   3G  50000    
3   slow-2G null     
4   2G  null     
5   offline null

这意味着在4G连接上，70%的0.7页加载时间少于1.5秒。我已尝试将脚本修改为：

SELECT
  SUM(bin.density)
WHERE
  SUM(bin.density) <= 0.7

但这是不允许的，所以尝试：

SELECT
  SUM(bin.density) AS RunningTotal
WHERE
  RunningTotal <= 0.7

也试过了

SELECT
  SUM(bin.density) OVER() AS RunningTotal
WHERE
  RunningTotal <= 0.7

但这也不行！如何使用嵌套数据集实现运行总计？然后让它输出bin.end时间

如果我不能让嵌套的数据集与SQL运行总计一起工作，那么我唯一的另一个选择就是展平数据集，并使用Python循环遍历每一行以计算结果。这是远远不够的性能

更新：基于Felipe Hoffa回答的解决方案

---

我想您需要一个子查询和一个累计总和：

with cte as (
      <your query here>
     )
select x.*
from (select cte.*, sum(density) over (order by density desc) as runningtotal
      from cte
     ) x
where runningtotal - density < 0.7 and runningtotal >= 0.7;

---

使用累积和并按连接对结果进行排序：

#standardSQL
SELECT ect, `end`, density
FROM (
  SELECT ect, `end`, density, ROW_NUMBER() OVER(PARTITION BY ect ORDER BY `end` DESC) rn
  FROM (
    SELECT  ect, bin.end, SUM(bin.density) OVER(PARTITION BY ect ORDER BY `end`) AS density 
    FROM (
      SELECT  effective_connection_type.name ect, first_contentful_paint.histogram
      FROM    `chrome-ux-report.chrome_ux_report.201710`
      WHERE    origin = 'http://example.com'
    ) , UNNEST(histogram.bin) AS bin
  )
  WHERE density < 0.7
) 
WHERE rn=1

---

输出bin.end值意味着什么？对于每个etc，如果组的密度至少为0.7，是否要返回bin.end某个子集的数组？如果您在问题中给出所需输出的示例将有所帮助。抱歉，请更新问题，并说明预期结果和bin.end time是什么。数据集有点混乱，这是谷歌的不是我的：你的问题不应该包含解决方案。如果您想分享您的解决方案，请删除该解决方案并发布答案。不过，您如何看待此输出bin.end？假设CTE先不检测是否满足绘制直方图bin？@ElliottBrossard。假设一切都会在CTE中完成。哇，这正是我所需要的！虽然当我手动计算时，它们不会相加：将4G的所有值相加到1000，得到的结果是：0.1504+0.1415+0.1262+0.0697+0.0473Ah，我相信这是将桌面和移动设备加在一起。这很容易解决。谢谢你的帮助！更新了我的最终解决方案。请点击此处链接：

#standardSQL
SELECT origin, form, ect, `end`, density
FROM (
  SELECT origin, form, ect, `end`, density, ROW_NUMBER() OVER(PARTITION BY ect ORDER BY `end` DESC) rn
  FROM (
    SELECT origin, form, ect, bin.end, SUM(bin.density) OVER(PARTITION BY ect ORDER BY `end`) AS density 
    FROM (
      SELECT origin, form_factor.name form, effective_connection_type.name ect, first_contentful_paint.histogram
      FROM    `chrome-ux-report.chrome_ux_report.201710`
      WHERE    origin = 'http://example.com' AND form_factor.name = 'phone'
    ) , UNNEST(histogram.bin) AS bin
  )
  WHERE density < 0.7
) 
WHERE rn=1

with cte as (
      <your query here>
     )
select x.*
from (select cte.*, sum(density) over (order by density desc) as runningtotal
      from cte
     ) x
where runningtotal - density < 0.7 and runningtotal >= 0.7;

#standardSQL
SELECT ect, `end`, density
FROM (
  SELECT ect, `end`, density, ROW_NUMBER() OVER(PARTITION BY ect ORDER BY `end` DESC) rn
  FROM (
    SELECT  ect, bin.end, SUM(bin.density) OVER(PARTITION BY ect ORDER BY `end`) AS density 
    FROM (
      SELECT  effective_connection_type.name ect, first_contentful_paint.histogram
      FROM    `chrome-ux-report.chrome_ux_report.201710`
      WHERE    origin = 'http://example.com'
    ) , UNNEST(histogram.bin) AS bin
  )
  WHERE density < 0.7
) 
WHERE rn=1