BigQuery 数组元素乘法

Question

菜鸟问题在这里：

我有一个 BQ table，其嵌套结构包含 2 个数组，x 和 y。我想创建一个新的 xy 数组或取消嵌套 2 个数组并创建 x、y 和 xy 值的扁平 table。

WITH
  tests AS (
  SELECT
  [  struct("test1" AS test,
        [0.1576,0.9706,0.9572,0.4854,0.8003,0.1419,0.4218,0.9157,0.7922,0.9595] AS x,
        [11,12,13,14,15,16,17,18,19,20] AS y),
    struct("test2" AS test,
        [0.8147,0.9058,0.1270,0.9134,0.6324,0.0975,0.2785,0.5469,0.9575, 0.9649] AS x,
        [11,12,13,14,15,16,17,18,19,20] AS y),
   struct("test3" AS test,
        [0.6557,0.0357,0.8491,0.9340,0.6787,0.7577,0.7431,0.3922,0.6555,0.1712] AS x,
        [11,12,13,14,15,16,17,18,19,20] AS y)
   ] AS measurements)


SELECT
  test, x,y
FROM
  tests t, unnest(t.measurements)

我想扩展上面的查询以获得一个扁平化的 table 测试编号，x，y 和 x*y 像这样，或类似的东西：

tests	x	y	x*y
test1	0.1576	11	1.7366
test1	0.9706	12	11.6472
test1	0.9572	13	12.4436
test1	0.4854	14	6.7956
...	...	...	...
test3	0.1712	20	3.4240

Answer 1

考虑以下方法

select test, x, y, round(x*y, 4) as x_multiply_y
from tests, unnest(measurements),
unnest(x) x with offset 
join unnest(y) y with offset 
using(offset)

如果应用于您问题中的示例数据 - 输出为

BigQuery 数组元素乘法

BigQuery Array Element Multiplicaton

sql

google-bigquery