使用shrink

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总结：实验过程1 建立测试表 5000万行数据2 删除其中40% 数据3 测试回收终止 与回收速度硬件环境i3 cpu 笔记本4G redhat 虚拟机 放在移动硬盘上USB2.0相连1 建立测试表create table test_shrink as select * from dba_objects 2 插入数据beginfor i in 1..1000loopinsert into test_shrinkselect * from dba_objects  ;commit ;end loop ;end  ;3 查看空间select bytes/1024/1024/1024 from user_segments  xwhere x.segment_name=upper('test_shrink')-----------------------  4.84472656254 查看行数515405445 删除一部分数据6 SQL> alter table SGW.TEST_SHRINK enable row movement;Table altered.Elapsed: 00:00:00.36SQL> alter table SGW.TEST_SHRINK shrink space;7 强行终止SQL> alter table SGW.TEST_SHRINK shrink space;alter table SGW.TEST_SHRINK shrink space*ERROR at line 1:ORA-01013: user requested cancel of current operationElapsed: 00:20:58.858 继续回收Elapsed: 00:02:02.51SQL> alter table SGW.TEST_SHRINK shrink space;Table altered.Elapsed: 00:44:44.509 查看结果SQL> select bytes/1024/1024/1024 from dba_segments  x  2    3  where x.segment_name=upper('test_shrink');BYTES/1024/1024/1024--------------------          3.27655029
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