move或rebuild lob分区对象

当使用如下语法移动或重建一个lob分区对象，将报错：

SQL> alter table SHOW_LOB_STORAGE move lob(DDD) store as (tablespace PARTFORLOB03);

ORA-14511: cannot perform operation on a partitioned object

 

正确的语法如下：

alter table <table name> move partition <table partition name> <table partition tablespace_name> lob (<lob column name>) store as <optional lob partition name> (tablespace <lob tablespace name>);

alter table <table name> move partition <table partition name> <table partition tablespace_name> lob (<lob column name>) store as (tablespace <lob tablespace name>);

 

实验如下：

1、创建表空间

create tablespace part_01 datafile '+DATADG' size 30M;

create tablespace part_02 datafile '+DATADG' size 30M;

create tablespace part_03 datafile '+DATADG' size 30M;

create tablespace lob_01 datafile '+DATADG' size 30M;

create tablespace lob_02 datafile '+DATADG' size 30M;

create tablespace lob_03 datafile '+DATADG' size 30M;

2、创建lob表分区

create table t (aaa number(5), bbb varchar2(10), ccc number(5), ddd clob ) partition by range(aaa) (

partition p1 values less than (50) tablespace part_01 lob (ddd) store as (tablespace lob_01),

partition p2 values less than (100) tablespace part_02 lob (ddd) store as (tablespace lob_02),

partition p3 values less than (maxvalue) tablespace part_03 lob (ddd) store as (tablespace lob_03));

insert into t values (11,'a',111,'clob_a');

insert into t values (51,'b',222,'clob_b');

insert into t values (101,'c',333,'clob_c');

commit;

 3、查看lob分区信息

set pagesize 180

col segment_name format a25

col segment_type format a16

col tablespace_name format a13

col partition_name format a15

select segment_name, segment_type, tablespace_name, partition_name from user_segments order by segment_name, partition_name;

select partition_name, lob_partition_name, tablespace_name from user_lob_partitions where table_name = 'T';

select table_name,def_tablespace_name from user_part_tables;

select table_name,column_name,lob_name,lob_index_name from user_part_lobs;

select table_name,partition_name,tablespace_name from user_tab_partitions where table_name='T';

4、move或重建lob分区对象

1）只迁移表分区P2中的lob对象到表空间lob_03

alter table t move partition P2 lob(DDD) store as (tablespace lob_03);

2）迁移表分区P1中lob对象到表空间lob_03，且重命名lob对象名称

alter table t move partition P1 lob(DDD) store as SYS_LOB_P227_111 (tablespace lob_03);  

3）迁移表分区P3中的lob对象到表空间 lob_01中，且表分区P3的表空间迁移到表空间 part_02

alter table t move partition P3 tablespace part_02 lob(DDD) store as (tablespace lob_01);

4）如果增加新的分区，还会使用用户或表默认使用的表空间，需修改分区表的表空间attribute

alter table t modify default attributes tablespace part_new; 

select def_tablespace_name from user_part_tables where table_name='T';

注意：
1、move分区表的lob对象，不应该去查user_lobs视图，而是应该去查user_lob_partitions视图。
2、move包含有blob对象的分区表到新的表空间情形：
---将表分区、lob对象全move到单独一个新表空间tbs_new中，语法类似如下：
alter table t move partition p_1 tablespace tbs_new
lob (lob1) store as (tablespace tbs_new ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE )
lob (lob2) store as (tablespace tbs_new ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE );
......
alter table t move partition p_n tablespace tbs_new
lob (lob1) store as (tablespace tbs_new ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE )
lob (lob2) store as (tablespace tbs_new ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE );
---如果将每个表分区、每个lob对象分别存储不同的表空间，则如下：
alter table t move partition p_1 tablespace tbs_1_1
lob (lob1) STORE as (tablespace tbs_2_1 ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE )
lob (lob2) store as (tablespace tbs_3_1 ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE );
......
alter table t move partition p_n tablespace tbs_1_n
lob (lob1) STORE as (tablespace tbs_2_n ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE )
lob (lob2) store as (tablespace tbs_3_n ENABLE STORAGE IN ROW CHUNK 8K PCTVERSION 0 NOCACHE );
3、新的分区（如interval的自动生成的新分区）还是会使用原来的（move前）表空间，需要修改分区表的默认存储表空间的属性：
alter table t modify default attributes tablespace tbs_new;
select def_tablespace_name from user_part_tables where table_name='T';
此时，今后生成的新分区才会去新的表空间，而不是老的表空间。