ORA-01489: 字符串连接的结果太长 01489. 00000 - “字符串连接的结果太长” [重复]

Question

我有这个查询，但我得到一个 ORA-01489 错误：ORA-01489：字符串连接的结果太长 01489。00000 -“字符串连接的结果太长”，是否可以解决这个问题，也许设置一个系统变量？

SELECT "USER_PRIMARY_sector","LOGIN","FIRST_NAME","LAST_NAME","sector_ROLE"
FROM (
SELECT user_primary_sector,login, first_name,  last_name,
       LTRIM(MAX(SYS_CONNECT_BY_PATH(rights,' / '))
       KEEP (DENSE_RANK LAST ORDER BY curr),' / ') AS sector_ROLE
      FROM  
        (SELECT  login,
              first_name,  
              last_name,
              user_primary_sector,
              rights,
              ROW_NUMBER() OVER (PARTITION BY login ORDER BY rights) AS curr,
              ROW_NUMBER() OVER (PARTITION BY login ORDER BY rights) -1 AS prev
        FROM  (select   member0_.login,  member0_.first_name first_name, sector2.sector_name user_primary_sector,  member0_.last_name last_name,
                        CONCAT(CONCAT(sector.sector_name, ' - '), role3_.role_name) rights 
 from
  TLC_DEVICES.t_member member0_
 inner join  TLC_DEVICES.t_user member0_1_    on member0_.member_id=member0_1_.user_id
 inner join  TLC_DEVICES.t_playable_role playedrole1_    on member0_.member_id=playedrole1_.user_id
 inner join  TLC_DEVICES.t_sector_role sectorrole2_    on playedrole1_.sector_role_id=sectorrole2_.sector_role_id
 inner join  TLC_DEVICES.t_role role3_    on sectorrole2_.role_id=role3_.role_id
 inner join  TLC_DEVICES.t_sector sector    on sectorrole2_.sector_id=sector.sector_id
 inner join  TLC_DEVICES.t_sector sector2    on sector2.sector_id=member0_1_.primary_sector_id
 where    current_date between playedrole1_.start_date and playedrole1_.end_date
 order by sector.sector_name
  ))
GROUP BY login, first_name,  last_name, user_primary_sector
CONNECT BY prev = PRIOR curr AND login = PRIOR login
START WITH curr = 1
)
ORDER BY user_PRIMARY_sector, FIRST_NAME, LAST_NAME;

Answer 1

一种选择是将MAX_STRING_SIZE 系统变量设置为EXTENDED。 来自甲骨文documentation：

具有最大长度 size 个字节或字符的可变长度字符串。您必须为 VARCHAR2 指定大小。最小大小为 1 个字节或 1 个字符。最大尺寸为：

如果 MAX_STRING_SIZE = EXTENDED，则为 32767 个字节或字符
如果 MAX_STRING_SIZE = STANDARD，则为 4000 个字节或字符

因此，如果您的 MAX_STRING_SIZE 当前设置为 STANDARD，那么如果您的连接字符串超过 4000 个字节或字符，您将收到 ORA-01489 错误。以下是您可以进行更改的方法：

ALTER SYSTEM SET MAX_STRING_SIZE = EXTENDED;

如果您的MAX_STRING_SIZE 已经设置为EXTENDED，那么您将不得不寻找另一种方法来处理如此长的字符串。