12c以前非分区表需要转换为分区, 如果不停业务的话可以使用在线重定义,只有在表进行切换的时候会有短暂的锁表。 12c 中alter table online clause 实现了表上现有的索引有效,又不停业务。
测试一：非分区表转分区表，索引转换为oracle内部规则。
-- 建非分区表
create table andy_clause as select * from user_objects where object_id is not null;
--创建非分区表索引
create index idx_oid on andy_clause( object_id );
create index idx_ctime_oname on andy_clause( created, object_name );
create bitmap index idx_b_otype on andy_clause(object_type);
--查看表索引
SQL>
col column_name for a40
SELECT index_name, column_name, descend,COLUMN_POSITION FROM user_ind_columns WHERE table_name = 'ANDY_CLAUSE';
INDEX_NAME COLUMN_NAME DESC COLUMN_POSITION
------------------------- ---------------------------------------- ---- ---------------
IDX_OID OBJECT_ID ASC 1
IDX_CTIME_ONAME CREATED ASC 1
IDX_CTIME_ONAME OBJECT_NAME ASC 2
IDX_B_OTYPE OBJECT_TYPE ASC 1
-- 查看索引状态
SQL>
col index_name for a25
select table_name,index_name,status,blevel,leaf_blocks from user_Indexes where table_name ='ANDY_CLAUSE';
TABLE_NAME INDEX_NAME STATUS BLEVEL LEAF_BLOCKS
------------------------- ------------------------- -------- ---------- -----------
ANDY_CLAUSE IDX_OID VALID 0 1
ANDY_CLAUSE IDX_CTIME_ONAME VALID 0 1
ANDY_CLAUSE IDX_B_OTYPE VALID 0 1
--转换当前表为分区以 object_id 字段, interval分区表，直接 update index，使用ORACLE有自己的索引转换规则。
SQL>
alter table andy_clause modify
partition by range (object_id) interval (5)
(
partition p1 values less than (73527)
) online
update indexes;
Table altered.
说明：update index ,没有指定写local 或global选项, ORACLE有自己的索引转换规则
--查看表索引
SQL>
col column_name for a40
SELECT index_name, column_name, descend,COLUMN_POSITION FROM user_ind_columns WHERE table_name = 'ANDY_CLAUSE';
INDEX_NAME COLUMN_NAME DESC COLUMN_POSITION
------------------------- ---------------------------------------- ---- ---------------
IDX_OID OBJECT_ID ASC 1
IDX_CTIME_ONAME CREATED ASC 1
IDX_CTIME_ONAME OBJECT_NAME ASC 2
IDX_B_OTYPE OBJECT_TYPE ASC 1
-- 查看索引状态
SQL>
col TABLE_NAME for a25
col index_name for a25
select table_name,index_name,INDEX_TYPE,status,blevel,leaf_blocks from user_Indexes where table_name ='ANDY_CLAUSE';
TABLE_NAME INDEX_NAME STATUS BLEVEL LEAF_BLOCKS
------------------------- ------------------------- -------- ---------- -----------
ANDY_CLAUSE IDX_OID N/A 0 4
ANDY_CLAUSE IDX_CTIME_ONAME VALID 0 1
ANDY_CLAUSE IDX_B_OTYPE N/A 0 4
SQL> COL INDEX_OWNER FOR A20;
SQL> select INDEX_OWNER,index_name,status,blevel,leaf_blocks from dba_ind_partitions where INDEX_OWNER='C##ANDY'and Index_name='IDX_OID';
INDEX_OWNER INDEX_NAME STATUS BLEVEL LEAF_BLOCKS
-------------------- ------------------------- -------- ---------- -----------
C##ANDY IDX_OID USABLE 0 1
C##ANDY IDX_OID USABLE 0 1
C##ANDY IDX_OID USABLE 0 1
C##ANDY IDX_OID USABLE 0 1
SQL>
COL INDEX_OWNER FOR A20;
col index_name for a25
select INDEX_OWNER,index_name,status,blevel,leaf_blocks from dba_ind_partitions where INDEX_OWNER='C##ANDY'and Index_name='IDX_B_OTYPE';
INDEX_OWNER INDEX_NAME STATUS BLEVEL LEAF_BLOCKS
-------------------- ------------------------- -------- ---------- -----------
C##ANDY IDX_B_OTYPE USABLE 0 1
C##ANDY IDX_B_OTYPE USABLE 0 1
C##ANDY IDX_B_OTYPE USABLE 0 1
C##ANDY IDX_B_OTYPE USABLE 0 1
说明：user_Indexes 是主要计量一个index的相关信息的，如果分区索引为local index 它不能记录状态，就为 N/A ，分区 local index要用视图 dba_ind_partitions 查状态。
-- 查看分区情况
SQL>
select table_name,partition_name,PARTITION_POSITION,tablespace_name,HIGH_VALUE from user_tab_partitions where table_name='ANDY_CLAUSE';
TABLE_NAME PARTITION_NAME PARTITION_POSITION TABLESPACE_NAME HIGH_VALUE
------------------------- ------------------------- ------------------ ------------------------------ -----------
ANDY_CLAUSE P1 1 USERS 73527
ANDY_CLAUSE SYS_P341 2 USERS 73532
ANDY_CLAUSE SYS_P343 3 USERS 73592
ANDY_CLAUSE SYS_P342 4 USERS 73597
测试二：非分区表转分区表，索引转换为自己设定规则。
-- 建非分区表
SQL> create table andy_clause02 as select * from user_objects where object_id is not null;
--创建非分区表索引
SQL>
create index idx_oid on andy_clause02( object_id );
create index idx_ctime_oname on andy_clause02( created, object_name );
create bitmap index idx_b_otype on andy_clause02(object_type);
--转换当前表为分区以 object_id 字段, interval分区表，update indexes 时，自己指定local 或global选项
SQL>
alter table andy_clause02 modify
partition by range (object_id) interval (5)
(
partition p1 values less than (73527)
) online
update indexes
( idx_oid local,
idx_ctime_oname global partition by range (created)
(
partition ix2_p1 values less than (date '2017-05-01'),
partition ix2_p2 values less than (maxvalue)
)
);
Table altered.
--查看表索引
SQL>
col index_name for a25
col COLUMN_NAME for a25
SELECT index_name, column_name, descend,COLUMN_POSITION FROM user_ind_columns WHERE table_name = 'ANDY_CLAUSE02';
INDEX_NAME COLUMN_NAME DESC COLUMN_POSITION
------------------------- ------------------------- ---- ---------------
IDX_OID OBJECT_ID ASC 1
IDX_CTIME_ONAME CREATED ASC 1
IDX_CTIME_ONAME OBJECT_NAME ASC 2
IDX_B_OTYPE OBJECT_TYPE ASC 1
-- 查看索引状态
SQL>
col index_name for a25
col TABLE_NAME for a25
select table_name,index_name,status,blevel,leaf_blocks from user_Indexes where table_name ='ANDY_CLAUSE02';
TABLE_NAME INDEX_NAME STATUS BLEVEL LEAF_BLOCKS
------------------------- ------------------------- -------- ---------- -----------
ANDY_CLAUSE02 IDX_OID N/A 1 113
ANDY_CLAUSE02 IDX_CTIME_ONAME N/A 2 432
ANDY_CLAUSE02 IDX_B_OTYPE N/A 1 3