alter table move & shrink space(1)

1.move

analyze table GC.R_WIP_KEYPARTS_T compute statistics;

 

SELECT BLOCKS,EMPTY_BLOCKS FROM DBA_TABLES

WHERE OWNER='GC' AND TABLE_NAME='R_WIP_KEYPARTS_T';

BLOCKS:137452

EMPTY_BLOCKS:1812

 

SELECT BLOCKS FROM DBA_SEGMENTS

WHERE SEGMENT_NAME='R_WIP_KEYPARTS_T';

BLOCKS:139264

 

DELETE from GC.R_WIP_KEYPARTS_T where rownum<5000;

這是數據被刪除，但HWM不會下降。

 

select count(distinct dbms_rowid.rowid_block_number(rowid)) from GC.R_WIP_KEYPARTS_T;

可以看到當前行所占的block數。肯定比BLOCKS:137452少