RANGE-HASH - PolarDB - Alibaba Cloud Documentation Center

This topic describes how to create a range-hash partitioned table.

Syntax

The following statement is used to create one or more range-hash partitioned tables. Partitions are of the RANGE [COLUMNS] type. Subpartitions are of the HASH or KEY type.

CREATE TABLE [ schema. ]table_name
 table_definition
   PARTITION BY RANGE {(expr)  COLUMNS(column_list)}
   SUBPARTITION BY {[LINEAR] HASH(expr) [SUBPARTITIONS number]
    [LINEAR] KEY [ALGORITHM={1  2}] (column_list)}
   (partition_definition [, partition_definition] ...);

partition_definition is:

 PARTITION partition_name
        VALUES LESS THAN {(expr  value_list)  MAXVALUE}
        (subpartition_definition [, subpartition_definition] ...)

subpartition_definition is:

SUBPARTITION subpartition_name

Parameters

Parameter	Description
expr	The expression of the partition. It must be of the INT type. The string type is not supported.
column_list	The list of partition key columns. Expressions are not supported.
number	The number of subpartitions.
value	The boundary value of the partition.
value_list	The list of the boundary values of the partitions. It is used in RANGE COLUMNS().
MAXVALUE	The maximum value of the partition.
partition_name	The name of the partition. The name must be unique within the table.
subpartition_name	The name of the subpartition. The name must be unique within the table.

Examples

Create a range-hash partitioned table:

CREATE TABLE sales_range_hash
(
  s_id        varchar(20),
  dept_no     INT,
  part_no     INT,
  country     varchar(20),
  date        DATE,
  amount      INT,
  primary key (s_id, date)
)
PARTITION BY RANGE COLUMNS(date)
SUBPARTITION BY KEY(s_id) SUBPARTITIONS 3
(
  PARTITION p1 VALUES LESS THAN('2023-01-01'),
  PARTITION p2 VALUES LESS THAN('2023-02-01'),
  PARTITION p3 VALUES LESS THAN('2023-03-01'),
  PARTITION p4 VALUES LESS THAN('2023-04-01')
);