Oracle 12C 新特性之move (非分区表)table online
以前版本中move table不能够online, move 会引rowid改变使对应的索引失效。 12c 中 alter table move online不会对新事务阻塞同时会自动的维护索引的有效性。
-- 创建实验表
SQL> create table andy_move (id int,name varchar2(10));
Table created.
-- 插入数据
SQL>
begin
for i in 1 .. 39 loop
insert into andy_move values(i,'andyi');
end loop ;
commit;
end;
/
PL/SQL procedure successfully completed.
-- 创建索引
SQL> create index idx_andy_id on andy_move(id);
Index created.
-- 查看索引状态
SQL>
col index_name for a25
select table_name,index_name,status,blevel,leaf_blocks,orphaned_entries from user_Indexes where index_name ='IDX_ANDY_ID';
TABLE_NAME INDEX_NAME STATUS BLEVEL LEAF_BLOCKS ORP
------------------------- ------------------------- -------- ---------- ----------- ---
ANDY_MOVE IDX_ANDY_ID VALID 0 0 NO
-- move online 非分区表,带 online 参数
SQL> alter table andy_move move online;
Table altered.
-- 查看索引状态
SQL>
col index_name for a25
select table_name,index_name,status,blevel,leaf_blocks,orphaned_entries from user_Indexes where index_name ='IDX_ANDY_ID';
TABLE_NAME INDEX_NAME STATUS BLEVEL LEAF_BLOCKS ORP
------------------------- ------------------------- -------- ---------- ----------- ---
ANDY_MOVE IDX_ANDY_ID VALID 0 0 NO
-- move online 分区表 报错
SQL> alter table p_andy move online;
alter table p_andy move online
*
ERROR at line 1:
ORA-14808: table does not support ONLINE MOVE TABLE
-- move 非分区表 ,不带 online 参数
delete from andy_move where id>10 and id<20;
SQL> alter table andy_move move;
Table altered.
-- 查看索引状态
SQL>
col index_name for a25
select table_name,index_name,status,blevel,leaf_blocks,orphaned_entries from user_Indexes where index_name ='IDX_ANDY_ID';
TABLE_NAME INDEX_NAME STATUS BLEVEL LEAF_BLOCKS ORP
------------------------- ------------------------- -------- ---------- ----------- ---
ANDY_MOVE IDX_ANDY_ID UNUSABLE 0 1 NO