PolarDB:CREATE TABLE ... PARTITION BY HASH

Create hash partitions

Syntax

CREATE TABLE ... PARTITION BY HASH (part_params) PARTITIONS number ;

The following table describes the parameters that are used in the syntax.

The following example shows the corresponding statement:

CREATE TABLE part_hash (deptno NUMBER, deptname VARCHAR(32))
     PARTITION BY HASH(deptno) PARTITIONS 4;

Create hash subpartitions

Syntax

CREATE TABLE ... PARTITION BY part_strategy ( part_params )  SUBPARTITION BY HASH ( part_params)  SUBPARTITIONS number ( table_partitions_list );

The following table describes the parameters that are used in the syntax.

• The partitioning type is RANGE and the subpartitioning type is HASH. The following example shows the corresponding statement:

   CREATE TABLE part_test
    ( prod_id       NUMBER(6), 
    cust_id       NUMBER, 
    time_id       DATE, 
    channel_id    CHAR(1), 
    promo_id      NUMBER(6), 
    quantity_sold NUMBER(3), 
    amount_sold   NUMBER(10,2)
    )
   PARTITION BY RANGE (time_id) SUBPARTITION BY HASH (cust_id)
    SUBPARTITIONS 4
   ( PARTITION sales_q1_2006 VALUES LESS THAN (TO_DATE('01-APR-2006','dd-MON-yyyy'))(
          SUBPARTITION q1_europe,
          SUBPARTITION q1_asia ,
          SUBPARTITION q1_americas
         ), 
   PARTITION sales_q2_2006 VALUES LESS THAN (TO_DATE('01-JUL-2006','dd-MON-yyyy')), 
   PARTITION sales_q3_2006 VALUES LESS THAN (TO_DATE('01-OCT-2006','dd-MON-yyyy')), 
   PARTITION sales_q4_2006 VALUES LESS THAN (TO_DATE('01-JAN-2007','dd-MON-yyyy'))
   );

• Both the partitioning type and the subpartitioning type is HASH. The following example shows the corresponding statement:

  CREATE TABLE part_test
    ( prod_id       NUMBER(6), 
    cust_id       NUMBER, 
    time_id       DATE, 
    channel_id    CHAR(1), 
    promo_id      NUMBER(6), 
    quantity_sold NUMBER(3), 
    amount_sold   NUMBER(10,2)
    )
  PARTITION BY HASH (prod_id) SUBPARTITION BY HASH (cust_id) 
    PARTITIONS 4 SUBPARTITIONS 4;

Related documentation

CREATE TABLE... PARTITION BY