将多行组合为一个

Question

我正在尝试在project_id匹配时将多个名称跨行组合到一列。我开始自我加入，但无法按照我想要的方式工作，我很确定有一个函数或cte可以做到这一点更容易。要求方向。使用db2。

到目前为止，这是我无法正常工作并产生-104错误。

  (

        SELECT 
                        DP.D_P_ID, DP.project_name,
                        DU2.NAME_LAST CONCAT ', ' CONCAT DU2.NAME_FIRST AS 
                        FROM Fact_table as FAT 
                        INNER JOIN D_P DP ON FAT.D_P_ID = DP.D_P_ID
                        INNER JOIN B_U_P BUP on DP.D_P = BUP.D_P_ID
                        INNER JOIN D_U DU2 ON BUP.D_U_ID = DU2.D_U_ID
                        INNER JOIN D_Date DD ON FAT.START_DATE_ID = DD.DATE_KEY
                        INNER JOIN D_A DA ON FAT.D_A_ID = DA.D_A_ID
                        WHERE  ((    (DD.DATE_VALUE >= '2013-01-01')
                                OR (DD.DATE_VALUE < '2014-01-01')
                                OR (DD.DATE_VALUE <= '2013-01-01')))
                                AND DA.M_NAME = 'Mandy'
                                AND BUP.USER_FLAG = 'Y'

                        GROUP BY  DP.D_P_ID, DP.project_name, DU2.NAME_LAST CONCAT ', ' CONCAT DU2.NAME_FIRST
                        ORDER BY DP.project_name 
             )  PI1      

                 join 

                        (
                                SELECT 
                        DP.D_P_ID, DP.project_name,
                        DU2.NAME_LAST CONCAT ', ' CONCAT DU2.NAME_FIRST AS 
                        FROM Fact_table as FAT 
                        INNER JOIN D_P DP ON FAT.D_P_ID = DP.D_P_ID
                        INNER JOIN B_U_P BUP on DP.D_P = BUP.D_P_ID
                        INNER JOIN D_U DU2 ON BUP.D_U_ID = DU2.D_U_ID
                        INNER JOIN D_Date DD ON FAT.START_DATE_ID = DD.DATE_KEY
                        INNER JOIN D_A DA ON FAT.D_A_ID = DA.D_A_ID
                        WHERE  ((    (DD.DATE_VALUE >= '2013-01-01')
                                OR (DD.DATE_VALUE < '2014-01-01')
                                OR (DD.DATE_VALUE <= '2013-01-01')))
                                AND DA.M_NAME = 'Mandy'
                                AND BUP.USER_FLAG = 'Y'

                        GROUP BY  DP.D_P_ID, DP.project_name, DU2.NAME_LAST CONCAT ', ' CONCAT DU2.NAME_FIRST
                        ORDER BY DP.project_name 
                        ) PI2 on PI1.d_p_id = PI2.d_p_id 

数据示例：

这是我需要的结果：

Answer 1

在外部选择使用像

这样的东西

select d_p_id, project_name, listagg(admin, ',')
from (...)
group by d_p_id, project_name

DB2 9.7及更高版本中提供的listagg()函数使用指定的分隔符通过组内的串联进行聚合。