Oracle中shrink space命令详解

2014-11-24 18:34:26 · 作者: · 浏览: 0

1 创建实验环境


1.1 创建ASSM的表空间


SQL> set serveroutput on


SQL> create tablespace ASSM datafile '/oradata/ltest/assm.dbf' size 10m autoextend on SEGMENT SPACE MANAGEMENT AUTO;


Tablespace created


SQL> select tablespace_name,


2 block_size,


3 extent_management,


4 allocation_type,


5 segment_space_management


6 from dba_tablespaces


7 where tablespace_name = 'ASSM';



TABLESPACE_NAME BLOCK_SIZE EXTENT_MANAGEMENT ALLOCATION_TYPE SEGMENT_SPACE_MANAGEMENT


--------------- ---------- ----------------- --------------- ------------------------


ASSM 8192 LOCAL SYSTEM AUTO


1.2 建表


SQL> create table my_objects tablespace assm as select * from all_objects;


Table created


SQL> select count(*) from my_objects;


COUNT(*)


----------


49903


2 实验前的信息


SQL> exec show_space('MY_OBJECTS');



Total Blocks ..........................768


Total Bytes ..........................6291456


Total MBytes ..........................6


Unused Blocks ..........................62


Unused Bytes ..........................507904


Unused KBytes ..........................496


Last Used Ext FileId....................7


Last Used Ext BlockId...................649


Last Used Block.........................66



The segment is analyzed below


FS1 Blocks (0-25) ....................0


FS2 Blocks (25-50) ....................0


FS3 Blocks (50-75) ....................0


FS4 Blocks (75-100) ....................0


Unformatted Blocks ....................0


Full Blocks ....................686



PL/SQL procedure successfully completed