Update问题(循环替代)?
各位大侠:
问题如下:有表X
date           name   instead
20070116   a         b
20070116   b         c
20070116   c         d
20070116   d         e
20070116   g         h
20070116   h         i
20070116   i         j
20070116   m         n

代表意义:   a <-b   b <-c   c <-d   d <-e   =>   a <-e
                    g <-h   h <-i   i <-j             =>   g <-j

用sql语句select出如下结果:
date           name   instead
20070116   a         e
20070116   g         j
20070116   m         n

谢谢!!!!


------解决方案--------------------
用start with ... connect by...
------解决方案--------------------
SQL> select * from x;

MYDATE MYNAME INSTEAD
----------- ------ -------
2007-1-16 a b
2007-1-16 b c
2007-1-16 c d
2007-1-16 d e
2007-1-16 g h
2007-1-16 h i
2007-1-16 i j
2007-1-16 m n

8 rows selected

SQL>
SQL> SELECT mydate, MIN(myname), MAX(INSTEAD)
2 FROM (SELECT * FROM x ORDER BY mydate, myname)
3 GROUP BY mydate, ascii(myname) - rownum
4 /

MYDATE MIN(MYNAME) MAX(INSTEAD)
----------- ----------- ------------
2007-1-16 a e
2007-1-16 g j
2007-1-16 m n
------解决方案--------------------
貌似可以写个函数，我用的是oracle