Question

我有一个包含2列的BigQuery表：

id|name
1|John
1|Tom
1|Bob
2|Jack
2|Tim

预期输出：按ID分组的连接名称

id|Text
1|John,Tom,Bob
2|Jack,Tim

Answer 1

对于BigQuery Standard SQL：

#standardSQL
--WITH yourTable AS (
--  SELECT 1 AS id, 'John' AS name UNION ALL
--  SELECT 1, 'Tom' UNION ALL
--  SELECT 1, 'Bob' UNION ALL
--  SELECT 2, 'Jack' UNION ALL
--  SELECT 2, 'Tim' 
--)
SELECT 
  id, 
  STRING_AGG(name ORDER BY name) AS Text 
FROM yourTable 
GROUP BY id

ORDER BY name中的STRING_CONCAT选项允许您输出已排序的名单列表，如下所示

id  Text     
1   Bob,John,Tom     
2   Jack,Tim

对于旧版SQL

#legacySQL
SELECT 
  id, 
  GROUP_CONCAT(name) AS Text   
FROM yourTable
GROUP BY id

如果你需要在这里输出排序列表，你可以在下面使用（正式 - BigQuery Legacy SQL无法保证获得排序列表 - 但对于大多数实际情况我都有 - 它有效）

#legacySQL
SELECT 
  id, 
  GROUP_CONCAT(name) AS Text 
FROM (
  SELECT id, name 
  FROM yourTable 
  ORDER BY name
)
GROUP BY id

Answer 2

您可以使用GROUP_CONCAT

SELECT id, GROUP_CONCAT(name) AS Text FROM <dataset>.<table> GROUP BY name

BigQuery - 将多行连接成一行

2 个答案: