SQL中聚类后字段数据串联字符串方法常见示例代码

SELECT group_column, GROUP_CONCAT(field_to_concatenate SEPARATOR ',') AS concatenated_string 
FROM table_name 
GROUP BY group_column; 

-- PostgreSQL / SQL Server 
SELECT group_column, STRING_AGG(field_to_concatenate, ',') AS concatenated_string 
FROM table_name 
GROUP BY group_column; 

SELECT group_column, STUFF( (SELECT ',' + field_to_concatenate 
FROM table_name t2 
WHERE t2.group_column = t1.group_column 
FOR XML PATH('')), 1, 1, '') AS concatenated_string 
    FROM table_name t1 
    GROUP BY group_column; 

SELECT group_column, STRING_AGG(field_to_concatenate, ',') AS concatenated_string 
FROM table_name 
GROUP BY group_column; 

WITH CTE AS 
( 
    SELECT group_column, 
           field_to_concatenate AS concatenated_string, 
           ROW_NUMBER() OVER (PARTITION BY group_column ORDER BY id) AS row_num 
    FROM table_name 
    UNION ALL 
    SELECT cte.group_column, 
           cte.concatenated_string + ',' + t.field_to_concatenate, 
           cte.row_num + 1 
           FROM CTE cte 
           JOIN table_name t 
           ON cte.group_column = t.group_column AND 
              t.row_num = cte.row_num + 1 
) 
SELECT group_column, 
       MAX(concatenated_string) AS concatenated_string 
FROM CTE 
GROUP BY group_column;