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  • oracle range分区表已经有了MAXVALUE 分区,如何添加分区?要不能删除MAXVALUE分区里的数据,不影响在线应用。

    来做个实验说明该问题:
    1.创建个分区表
    SQL> create table p_range_test
    2 (id number,name varchar2(100))
    3 partition by range(id)(
    4 partition t_p1 values less than (10),
    5 partition t_p2 values less than (20),
    6 partition t_p3 values less than (30)
    7 );
    Table created.

    2.查第一步创建好分区表的信息
    SQL> col TABLE_NAME for a20
    SQL> col partition_name for a20
    SQL> col HIGH_VALUE for a10
    SQL> col TABLESPACE_NAME for a15
    SQL> select table_name,partition_name,high_value,tablespace_name from user_tab_partitions where table_name='P_RANGE_TEST' order by partition_position;
    TABLE_NAME PARTITION_NAME HIGH_VALUE TABLESPACE_NAME
    -------------------- -------------------- ---------- ---------------
    P_RANGE_TEST T_P1 10 TP1
    P_RANGE_TEST T_P2 20 TP1
    P_RANGE_TEST T_P3 30 TP1
    从上面看出已有3个分区

    3.添加一个分区t_p4
    SQL> alter table p_range_test add partition t_p4 values less than(40);
    Table altered.
    顺序添加完成,当然这个不是题目所要完成的

    4.再第三步添加好分区的信息
    SQL> select table_name,partition_name,high_value,tablespace_name from user_tab_partitions where table_name='P_RANGE_TEST' order by partition_position;
    TABLE_NAME PARTITION_NAME HIGH_VALUE TABLESPACE_NAME
    -------------------- -------------------- ---------- ---------------
    P_RANGE_TEST T_P1 10 TP1
    P_RANGE_TEST T_P2 20 TP1
    P_RANGE_TEST T_P3 30 TP1
    P_RANGE_TEST T_P4 40 TP1
    从这个实验结果可以看到t_p4分区已经创建成功

    5.对于提出问题:如果在创建RANGE分区表的时候指定了maxvalue,不可以添加分区(需要使用split方法来处理)
    继续实验来验证是否可行 !!!

    6.创建带有maxvalue的分区表
    SQL> drop table p_range_test purge;
    create table p_range_test (id number,name varchar2(100))
    partition by range(id)(
    partition t_p1 values less than (10),
    partition t_p2 values less than (20),
    partition t_p3 values less than (30),
    partition t_pmax values less than (maxvalue));
    Table dropped.
    SQL> 2 3 4 5 6
    Table created.

    7.此时添加分区时会报如下的错误
    SQL> alter table p_range_test add partition t_p4 values less than(40);
    alter table p_range_test add partition t_p4 values less than(40)
    *
    ERROR at line 1:
    ORA-14074: partition bound must collate higher than that of the last partition
    添加分区失败?那有没有办法搞定呢,对于牛B的oracle来说肯定有办法了,处理方法就是使用split来搞!

    8.再查一下当前的分表的信息
    SQL> select table_name,partition_name,high_value,tablespace_name from user_tab_partitions where table_name='P_RANGE_TEST' order by partition_position;
    TABLE_NAME PARTITION_NAME HIGH_VALUE TABLESPACE_NAME
    -------------------- -------------------- ---------- ---------------
    P_RANGE_TEST T_P1 10 TP1
    P_RANGE_TEST T_P2 20 TP1
    P_RANGE_TEST T_P3 30 TP1
    P_RANGE_TEST T_PMAX MAXVALUE TP1

    9.注意,这步就是关键的一步!!!!!使用split完成上面没有完成的分区任务
    SQL> alter table p_range_test split partition t_pmax at (40) into (partition, partition t_pmax);
    Table altered.

    10.再查一下当前的分表的信息
    SQL> select table_name,partition_name,high_value,tablespace_name from user_tab_partitions where table_name='P_RANGE_TEST' order by partition_position;
    TABLE_NAME PARTITION_NAME HIGH_VALUE TABLESPACE_NAME
    -------------------- -------------------- ---------- ---------------
    P_RANGE_TEST T_P1 10 TP1
    P_RANGE_TEST T_P2 20 TP1
    P_RANGE_TEST T_P3 30 TP1
    P_RANGE_TEST SYS_P41 40 TP1
    P_RANGE_TEST T_PMAX MAXVALUE TP1
    搞定收工!!!

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  • 原文地址:https://www.cnblogs.com/chenjunjie/p/4720989.html
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