----------
1
tony@ORA11GR2> alter table t enable row movement;
Table altered.
tony@ORA11GR2> alter table t shrink space;
Table altered.
tony@ORA11GR2> delete from chained_rows;
1 row deleted.
tony@ORA11GR2> analyze table t list chained rows;
Table analyzed.
tony@ORA11GR2> select count(*) from chained_rows;
COUNT(*)
----------
0
tony@ORA11GR2> update t set y = rpad('*',2000,'*') where x = 2;
1 row updated.
tony@ORA11GR2> analyze table t list chained rows;
Table analyzed.
tony@ORA11GR2> select count(*) from chained_rows;
COUNT(*)
----------
1
tony@ORA11GR2> alter table t move;
Table altered.
tony@ORA11GR2> delete from chained_rows;
1 row deleted.
tony@ORA11GR2> analyze table t list chained rows;
Table analyzed.
tony@ORA11GR2> select count(*) from chained_rows;
COUNT(*)
----------
0
摘自 NowOrNever
|