DB2 SQL 实现行转列，列转行

列转行：
SELECT SERV_ID,
  LISTAGG(SERV_NAME,',')  
FROM MK.SERV 
GROUP BY SERV_ID

行转列：
WITH N  
  (
    STR,
    ORI,
    POS,
    PROD_ID 
  )
  AS  
  (
    ( SELECT CONCAT(PROD_REASON,','),
        1,
        POSSTR(CONCAT(PROD_REASON,','), ';'),
        PROD_ID 
      FROM MK.D_TRUE_NEW ) 
  UNION ALL SELECT STR,
              POS+1,
              LOCATE(';', STR, POS+1),
              PROD_ID 
            FROM N 
            WHERE LOCATE(';', STR, POS+1)>0 
            )
SELECT PROD_ID,
  SUBSTR(STR,ORI,