Question

参考此question我想手动创建多个列。

SELECT SPLIT(Titles) AS Title 
FROM (SELECT 'Title 1,Title 2,Title 3,Title 4' AS Titles)

我尝试过简单地添加这样的新列：

SELECT SPLIT(Titles) AS Title, SPLIT(Names) AS Name,FROM (SELECT 'Title 1,Title 2,Title 3,Title 4' AS Titles, 'Name 1,Name 2,Name 3,Name 4' AS NAMES)

然而，BQ向我显示以下错误：

Error: Cannot output multiple independently repeated fields at the same time. Found Title and Name

我认为这可能与BQ如何压扁结果有关，我发现了类似的问题here。不幸的是我无法转换我的代码。我只能使用Legacy SQL。

编辑：预期表应如下所示：

-- +---------+--------+
-- | Title   | Name   |
-- +---------+--------+
-- | Title 1 | Name 1 |
-- | Title 2 | Name 2 | 
-- | Title 3 | Name 3 |
-- | Title 4 | Name 4 |
-- +---------+--------+

Answer 1

以下是BigQuery Standard SQL

#standardSQL
WITH data AS (
  SELECT 'Title 1,Title 2,Title 3,Title 4' AS Titles, 'Name 1,Name 2,Name 3,Name 4' AS Names
)
SELECT 
  Title, 
  Name
FROM data, 
  UNNEST(SPLIT(Titles)) AS Title WITH OFFSET AS pos1, 
  UNNEST(SPLIT(Names)) AS Name WITH OFFSET AS pos2
WHERE pos1 = pos2  
ORDER BY Title

BigQuery Legacy SQL中的相同想法看起来更加浓密

#legacySQL
SELECT
  Title, Name
FROM FLATTEN((
  SELECT Title,  POSITION(Title) AS pos1
  FROM (
    SELECT SPLIT(Titles) AS Title
    FROM (SELECT 'Title 1,Title 2,Title 3,Title 4' AS Titles, 'Name 1,Name 2,Name 3,Name 4' AS Names)
  )
), pos1) AS titles
JOIN FLATTEN((
  SELECT Name, POSITION(Name) AS pos2
  FROM (
    SELECT SPLIT(Names) AS Name
    FROM (SELECT 'Title 1,Title 2,Title 3,Title 4' AS Titles, 'Name 1,Name 2,Name 3,Name 4' AS Names)
  )
), pos2) AS names
ON pos1 = pos2

BigQuery SPLIT手动创建表

1 个答案: