可能存在断点,查询出连续的记录来

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在ITPUB上有一则非常巧妙的SQL技巧，学习一下，记录在这里。

最初的问题是这样的:

我有一个表结构，
fphm,kshm
2014,00000001
2014,00000002
2014,00000003
2014,00000004
2014,00000005
2014,00000007
2014,00000008
2014,00000009
2013,00000120
2013,00000121
2013,00000122
2013,00000124
2013,00000125

(第二个字段内可能是连续的数据，可能存在断点。)
怎样能查询出来这样的结果,查询出连续的记录来。
就像下面的这样？
2014,00000001,00000005
2014,00000009,00000007
2013,00000120,00000122
2013,00000124,00000125

ITPUB上的朋友给出了一个非常巧妙的答案:

SQL> SELECT b.fphm, MIN (b.kshm) Start_HM, MAX (b.kshm) End_HM
2 FROM (SELECT a.*, TO_NUMBER (a.kshm - ROWNUM) cc
3 FROM (SELECT *
4 FROM t
5 ORDER BY fphm, kshm) a) b
6 GROUP BY b.fphm, b.cc
7 /
FPHM START_HM END_HM
---------- -------- --------
2013 00000120 00000122
2013 00000124 00000125
2014 00000001 00000005
2014 00000007 00000009

巧思妙想，就在一念之间。

create table t(fphm varchar2(4),kshm varchar2(8))

insert into t(fphm,kshm)
values(2014,'00000001');
insert into t(fphm,kshm)
values(2014,'00000002');
insert into t(fphm,kshm)
values(2014,'00000003');
insert into t(fphm,kshm)
values(2014,'00000004');
insert into t(fphm,kshm)
values(2014,'00000005');
insert into t(fphm,kshm)
values(2014,'00000007');
insert into t(fphm,kshm)
values(2014,'00000008');
insert into t(fphm,kshm)
values(2014,'00000009');
insert into t(fphm,kshm)
values(2013,'00000120');
insert into t(fphm,kshm)
values(2013,'00000121');
insert into t(fphm,kshm)
values(2013,'00000122');
insert into t(fphm,kshm)
values(2013,'00000124');
insert into t(fphm,kshm)
values(2013,'00000125');

SELECT b.fphm, MIN (b.kshm) Start_HM, MAX (b.kshm) End_HM
FROM (SELECT a.*, TO_NUMBER (a.kshm - ROWNUM) cc
FROM (SELECT *
FROM t
ORDER BY fphm, kshm) a) b
GROUP BY b.fphm, b.cc