google-bigquery - BigQuery SQL 运行总数

Question

知道如何在 BigQuery SQL 中计算运行总数吗？

id   value   running total
--   -----   -------------
1    1       1
2    2       3
3    4       7
4    7       14
5    9       23
6    12      35
7    13      48
8    16      64
9    22      86
10   42      128
11   57      185
12   58      243
13   59      302
14   60      362 

对于使用相关标量查询的传统 SQL 服务器来说，这不是问题:

SELECT a.id, a.value, (SELECT SUM(b.value)
                       FROM RunTotalTestData b
                       WHERE b.id <= a.id)
FROM   RunTotalTestData a
ORDER BY a.id;

或加入:

SELECT a.id, a.value, SUM(b.Value)
FROM   RunTotalTestData a,
       RunTotalTestData b
WHERE b.id <= a.id
GROUP BY a.id, a.value
ORDER BY a.id;

但我找不到让它在 BigQuery 中工作的方法......

Answer 1

2018 更新:原始问题中的查询现在无需修改即可使用。

#standardSQL
WITH RunTotalTestData AS (
  SELECT * FROM UNNEST([STRUCT(1 AS id, 1 AS value),(2,0),(3,1),(4,1),(5,2),(6,3)]) 
)

SELECT a.id, a.value, (SELECT SUM(b.value)
                       FROM RunTotalTestData b
                       WHERE b.id <= a.id) runningTotal
FROM   RunTotalTestData a
ORDER BY a.id;

2013 更新:您可以使用 SUM() OVER() 来计算运行总计。

在你的例子中:

SELECT id, value, SUM(value) OVER(ORDER BY id)
FROM [your.table]

一个工作示例:

SELECT word, word_count, SUM(word_count) OVER(ORDER BY word)
FROM [publicdata:samples.shakespeare]
WHERE corpus  = 'hamlet'
AND word > 'a' LIMIT 30;