如何手工回收段空间?

/*

　　create table --- emp1

　　delete

　　shrink space

*/

1、创建表emp1,构建大数据 

SQL> select count(*) from emp1;

  COUNT(*)
----------
    229376

SQL> select segment_name,blocks from user_segments where segment_name = 'EMP1';

SEGMENT_NAME                                           BLOCKS
-------------------------------------------------- ----------
EMP1                                                      384

2、删除表中数据，产生块的空洞

SQL> delete emp1 where empno in (7876,7369,7900,7499,7788);

81920 rows deleted.

SQL> commit;

Commit complete.

SQL> analyze table emp1 compute statistics;

Table analyzed.

SQL> select table_name,blocks from user_tables;

TABLE_NAME                         BLOCKS
------------------------------ ----------
EMP3                                  499
EMP1                                  338
EMP2                                  375
T                                       5
LIST1                                   0
COMPOSITE1                              0
RANGE2                               1256
RANGE1                                300
EMP                                   120

9 rows selected.

3、执行shrink space功能

SQL> alter table emp1 enable row movement;

Table altered.

SQL> alter table emp3 enable row movement;

Table altered.

SQL> alter table emp3 shrink space;

Table altered.

在这里出现了一个小插曲，我的表空间明明是采用ASSM管理的，可是在执行收缩的时候，还是会出现错误:

SQL> alter table emp1 shrink space;
alter table emp1 shrink space
*
ERROR at line 1:
ORA-10635: Invalid segment or tablespace type

此问题，留待以后解决.