老道关于分区表的管理（三） 维护篇

RANGE分区
1.1 RANGE分区

CREATE TABLE dao_partitions
   ( prod_id        NUMBER(6),
     insert_time    date  
   )
PARTITION BY RANGE (insert_time)
 (PARTITION SALES_1998 VALUES LESS THAN (TO_DATE('01-JAN-1999','DD-MON-YYYY')),
  PARTITION SALES_1999 VALUES LESS THAN (TO_DATE('01-JAN-2000','DD-MON-YYYY')),
  PARTITION SALES_2000 VALUES LESS THAN (TO_DATE('01-JAN-2001','DD-MON-YYYY'))
 );
1 无maxvalue分区下增加分区
SQL> alter table  dao_range_partition add PARTITION SALES_2001  VALUES LESS THAN (TO_DATE('01-JAN-2002','DD-MON-YYYY'));

Table altered.

SQL> select  DTP.TABLE_OWNER,DTP.TABLE_OWNER ,DTP.PARTITION_NAME
  2  from dba_tab_partitions DTP
  3  where table_owner='DAO'
  4  AND  TABLE_NAME='DAO_RANGE_PARTITION';

TABLE_OWNER  TABLE_OWNER     PARTITION_NAME
------------ --------------- --------------
DAO          DAO             SALES_1998
DAO          DAO             SALES_1999
DAO          DAO             SALES_2000
DAO          DAO             SALES_2001

2 增加max分区
SQL> ALTER TABLE  DAO_RANGE_PARTITION ADD PARTITION SALES_MAX  VALUES LESS THAN ( MAXVALUE );

Table altered.

SQL> select  DTP.TABLE_OWNER,DTP.TABLE_OWNER ,DTP.PARTITION_NAME
  2  from dba_tab_partitions DTP
  3  where table_owner='DAO'
  4  AND  TABLE_NAME='DAO_RANGE_PARTITION';

TABLE_OWNER  TABLE_OWNER PARTITION_NAME
------------------------------------------
DAO          DAO         SALES_1998
DAO          DAO         SALES_1999
DAO          DAO         SALES_2000
DAO          DAO         SALES_2001
DAO          DAO         SALES_MAX   

3 通过拆分maxvalue分区增加分区
SQL> alter table DAO_RANGE_PARTITION  split   partition SALES_MAX  at
    (TO_DATE(' 2003-01-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIAN'))
    into (partition SALES_2002 tablespace users ,partition SALES_MAX tablespace users );

Table altered.


4 通过drop maxvalue分区 加入分区


SQL> alter table DAO_RANGE_PARTITION drop partition SALES_MAX ;

Table altered.

SQL> select  DTP.TABLE_OWNER,DTP.TABLE_OWNER ,DTP.PARTITION_NAME
  2  from dba_tab_partitions DTP
  3  where table_owner='DAO'
  4  AND  TABLE_NAME='DAO_RANGE_PARTITION'
  5  ;

TABLE_OWNER  TABLE_OWNER  PARTITION_NAME
------------ ------------ ---------------
DAO          DAO          SALES_1998
DAO          DAO          SALES_1999
DAO          DAO          SALES_2000
DAO          DAO          SALES_2001
DAO          DAO          SALES_2002


SQL> alter table  dao_range_partition add PARTITION SALES_2003  VALUES LESS THAN (TO_DATE('01-JAN-2004','DD-MON-YYYY'));

Table altered

SQL> select  DTP.TABLE_OWNER,DTP.TABLE_OWNER ,DTP.PARTITION_NAME
  2  from dba_tab_partitions DTP
  3  where table_owner='DAO'
  4  AND  TABLE_NAME='DAO_RANGE_PARTITION';

TABLE_OWNER TABLE_OWNER  PARTITION_NAME
----------- ------------ ----------------
DAO         DAO          SALES_1998
DAO         DAO          SALES_1999
DAO         DAO          SALES_2000
DAO         DAO          SALES_2001
DAO         DAO          SALES_2002
DAO         DAO          SALES_2003


SQL>  ALTER TABLE  DAO_RANGE_PARTITION ADD PARTITION SALES_MAX  VALUES LESS THAN ( MAXVALUE );

Table altered.

2 分区删除
SQL> alter table DAO_RANGE_PARTITION drop partition SALES_MAX ;

Table altered.

SQL> select  DTP.TABLE_OWNER,DTP.TABLE_OWNER ,DTP.PARTITION_NAME
  2  from dba_tab_partitions DTP
  3  where table_owner='DAO'
  4  AND  TABLE_NAME='DAO_RANGE_PARTITION'
  5  ;

TABLE_OWNER  TABLE_OWNER  PARTITION_NAME
------------ ------------ ---------------
DAO          DAO          SALES_1998
DAO          DAO          SALES_1999
DAO          DAO          SALES_2000
DAO          DAO          SALES_2001
DAO          DAO          SALES_2002
3 分区truncate 
SQL> alter table DAO_RANGE_PARTITION truncate partition  SALES_2002 ;

Table truncated.

4 分区拆分
SQL> alter table DAO_RANGE_PARTITION  split   partition SALES_MAX  at
    (TO_DATE(' 2003-01-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIAN'))
    into (partition SALES_2002 tablespace users ,partition SALES_MAX tablespace users );

Table altered.

5 分区合并
SQL>  select DTP.TABLE_OWNER, DTP.TABLE_NAME, DTP.PARTITION_NAME
  2     from dba_tab_partitions DTP
  3    where table_owner = 'DAO'
  4      AND TABLE_NAME = 'DAO_RANGE_PARTITION';

TABLE_OWNER        TABLE_NAME             PARTITION_NAME
----------------------------------------- ---------------
DAO                DAO_RANGE_PARTITION    SALES_1998
DAO                DAO_RANGE_PARTITION    SALES_1999
DAO                DAO_RANGE_PARTITION    SALES_2000
DAO                DAO_RANGE_PARTITION    SALES_2001
DAO                DAO_RANGE_PARTITION    SALES_2002
DAO                DAO_RANGE_PARTITION    SALES_2003
DAO                DAO_RANGE_PARTITION    SALES_MAX

7 rows selected.
 
 
SQL> ALTER TABLE DAO_RANGE_PARTITION MERGE PARTITIONS  SALES_1998,SALES_1999  INTO  PARTITION SALES_1999 ;

Table altered.


SQL>  select  DTP.TABLE_OWNER,DTP.TABLE_NAME ,DTP.PARTITION_NAME from dba_tab_partitions DTP where table_owner='DAO'   AND  TABLE_NAME='DAO_RANGE_PARTITION';

TABLE_OWNER     TABLE_NAME                     PARTITION_NAME
--------------- ------------------------------ --------------
DAO             DAO_RANGE_PARTITION            SALES_1999
DAO             DAO_RANGE_PARTITION            SALES_2000
DAO             DAO_RANGE_PARTITION            SALES_2001
DAO             DAO_RANGE_PARTITION            SALES_2002
DAO             DAO_RANGE_PARTITION            SALES_2003
DAO             DAO_RANGE_PARTITION            SALES_MAX

6 rows selected.


6 分区交换

SQL>  select  DTP.TABLE_OWNER,DTP.TABLE_NAME ,DTP.PARTITION_NAME from dba_tab_partitions DTP where table_owner='DAO'   AND  TABLE_NAME='DAO_RANGE_PARTITION';

TABLE_OWNER    TABLE_NAME            PARTITION_NAME
-------------- --------------------- ---------------
DAO            DAO_RANGE_PARTITION   SALES_1999
DAO            DAO_RANGE_PARTITION   SALES_2000
DAO            DAO_RANGE_PARTITION   SALES_2001
DAO            DAO_RANGE_PARTITION   SALES_2002
DAO            DAO_RANGE_PARTITION   SALES_2003
DAO            DAO_RANGE_PARTITION   SALES_MAX


2	HASH分区

SQL> insert into  dao_test_hash 
  2  select level,to_char(level)||to_char(level)
  3  from dual
  4  connect by level<=100;

100 rows created.

SQL> commit ;

Commit complete.


SQL> select count(*), 'all'
  2    from dao_test_hash
  3  union all
  4  select count(*), 'p1'
  5    from dao_test_hash partition (p1)
  6  union all
  7  select count(*), 'p2' 
  8     from dao_test_hash partition (p2);

  COUNT(*) 'AL
---------- ---
       100 all
        45 p1
        55 p2



1 增加分区
SQL> alter table dao_test_hash add partition p3 ;

Table altered.

SQL> select count(*), 'all'
  2    from dao_test_hash
  3  union all
  4  select count(*), 'p1'
  5    from dao_test_hash partition(p1)
  6  union all
  7  select count(*), 'p2' 
  8     from dao_test_hash partition(p2)
  9  union all   
 10  select count(*), 'p3' 
 11     from dao_test_hash partition(p3);   

  COUNT(*) 'AL
---------- ---
       100 all
        20 p1
        55 p2
        25 p3


SQL> alter table dao_test_hash add partition p4 ;


Table altered.

SQL> SQL> select count(*), 'all'
  2    from dao_test_hash
  3  union all
  4  select count(*), 'p1'
  5    from dao_test_hash partition(p1)
  6  union all
  7  select count(*), 'p2' 
  8     from dao_test_hash partition(p2)
  9  union all   
 10  select count(*), 'p3' 
 11     from dao_test_hash partition(p3)
 12  union all
 13  select count(*), 'p4' 
 14     from dao_test_hash partition(p4);

  COUNT(*) 'AL
---------- ---
       100 all
        20 p1
        28 p2
        25 p3
        27 p4

SQL> select dao_xx+1,count(*)
  2  from
  3  (select ora_hash(level,3,0) dao_xx
  4  from dual 
  5  connect by level <=100 )
  6  group by dao_xx ;

  DAO_XX+1   COUNT(*)
---------- ----------
         2         28
         3         25
         4         27
20
Hash 分区数据分布函数使用的是ORA_HASH函数
3 列表分区
基本与范围分区相同，参见范围分区