在Oracle数据库中,创建Hash分区是一种将表数据基于哈希函数均匀分布到不同分区的方法。这有助于提升查询性能,尤其是在处理大数据集时。以下是创建Hash分区的步骤和示例代码: 1. 创建分区表 首先,你需要定义一个分区表。在定义表时,你需要指定分区键(partition key)以及分区的数量。 sql CREATE TABLE hash_partition...
ALTER TABLE hash_example ADD PARTITION part03; --hash partitioned table 新增partition时,现有表的中所有data都有重新计算hash值,然后重新分配到分区中。 --所以被重新分配的分区的 indexes需要rebuild --增加subpartition ALTER TABLE range_hash_example MODIFY PARTITION part_1 ADD SUBPARTITION part_1_sub_4;...
create table hash_part1 ( id number, name varchar2(32)) partition by hash(id) ( partition p1 tablespace tbs1, partition p2 tablespace tbs2 ); 也可以仅指定哈希分区的数量,此时Oracle会自动为每个分区生成名字: create table hash_part2 ( id number, name varchar2(32)) partition by hash(id) ...
1CREATETABLEhash_example(2hash_key_column DATE,3DATAVARCHAR2(20)4) PARTITIONBYHASH(hash_key_cloumn)5(6PARTITION part01 ,7PARTITION part028); 4、组合分区表 1CREATETABLErange_hash_example(2range_column_key DATE,3hash_column_keyINT,4DATAVARCHAR2(20)5)6PARTITIONBYRANGE(range_column_key)7SUBP...
PARTITION PR2 VALUES ('NO') ); Hash Partitioning In this oracle used the hashing algorithm to decide the physical placement of data. Hash partitioning will distribute data evenly across a fixed number of partitions. CREATE TABLE EXP_HASH
CREATE TABLE scubagear (id NUMBER, name VARCHAR2 (60)) PARTITION BY HASH (id) PARTITIONS 4 STORE IN (gear1, gear2, gear3, gear4); 1. 2. 3. 4. 5. 6. 什么时候使用list分区 你要控制数据分布的时候,使用list分区,多列的分区对于List是不支持的,分区列只能有1列。
PARTITION BY HASH (COL) 1. ( 1. PARTITION PART01 TABLESPACE HASH_TS01, 1. PARTITION PART02 TABLESPACE HASH_TS02, 1. PARTITION PART03 TABLESPACE HASH_TS03 1. ) 1. 简写: 1. CREATE TABLE emp 1. ( 1. empno NUMBER (4), 1.
PARTITION part01 ,ITPUB个人空间9l_m_O B7@_a PARTITION part02ITPUB个人空间2v_u_E2X'p4D_~1Q_\ p0J ); 4、组合分区表ITPUB个人空间_J5l/@7a;~_Y_f.t CREATE TABLE range_hash_example(ITPUB个人空间8D P_o_m:O_V range_column_key DATE, _k R:e_eD+t_a0hash_column_key INT,ITPUB个人...
Oracle offers two types of global partitioned index: range partitioned and hash partitioned. (1)Global Range Partitioned Indexes Global range partitioned indexes are flexible in that the degree of partitioning and the partitioning key are independent from the table’s partitioning method. They are...
Database version - 9.2.0.8 Create Partitioned table which PARTITION BY RANGE (EOW_DATE column which is of data type date) and then SUBPARTITION BY HASH (store column of number datatype) Below are the list of columns Name Null? Type ...