SQL> select count(*) from t;
COUNT(*)
----------
126264
SQL> delete from t where object_id<14000;
已删除96216行。
SQL> commit;
提交完成。
SQL> analyze table t compute statistics;
表已分析。
SQL> select blocks,empty_blocks,num_rows from dba_tables where table_name='T' an
d owner='SYS';
BLOCKS EMPTY_BLOCKS NUM_ROWS
---------- ------------ ----------
1756 36 30048
SQL> select count(distinct dbms_rowid.rowid_block_number(rowid)) from t;
COUNT(DISTINCTDBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID))
---------------------------------------------------
605
SQL> select round(100*605/1756,2) from dual;
ROUND(100*605/1756,2)
---------------------
34.45
SQL>
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