Help Center/ GaussDB(for MySQL)/ Kernels/ Common Kernel Functions/ Enhanced Partitioned Tables/ Subpartitioning/ KEY-RANGE
Updated on 2024-09-06 GMT+08:00
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KEY-RANGE

Syntax

The following statement is used to create one or more KEY-RANGE partitioned tables where each partition may contain one or more subpartitions:

CREATE TABLE [ schema. ]table_name
 table_definition
   PARTITION BY [LINEAR] KEY (column_list)
   SUBPARTITION BY RANGE {(expr) | COLUMNS(column_list)}
   (partition_definition [, partition_definition] ...);

partition_definition is:

PARTITION partition_name
    (subpartition_definition [, subpartition_definition] ...)

subpartition_definition is:

SUBPARTITION subpartition_name
   VALUES LESS THAN {value | value_list | MAXVALUE}
Table 1 Parameters

Parameter

Description

table_name

The name of the table to be created.

expr

The expression of the partition. Currently, only the INT type is supported.

column_list

The list of partition key columns. It is used in RANGE COLUMNS(). Expressions are not supported.

value

The boundary value of the partition.

value_list

The list of the values of the partition key columns. It is used in LIST COLUMNS().

MAXVALUE

The maximum value of the partition.

partition_name

subpartition_name

The name of the partition. The name must be unique within the table.

The name of the subpartition. The name must be unique within the table.

Example

Create a KEY-RANGE partitioned table:

CREATE TABLE tbl_key_range
(
    col1 INT,
    col2 INT,
    col3 varchar(20),
    col4 DATE
)
PARTITION BY KEY(col1)
    SUBPARTITION BY RANGE COLUMNS(col4)
(
  PARTITION  p0(
    SUBPARTITION p0_q1_2023 VALUES LESS THAN('2023-04-01'),
    SUBPARTITION p0_q2_2023 VALUES LESS THAN('2023-07-01'),
    SUBPARTITION p0_q3_2023 VALUES LESS THAN('2023-10-01'),
    SUBPARTITION p0_q4_2023 VALUES LESS THAN('2024-01-01')
  ),
  PARTITION  p1(
    SUBPARTITION p1_q1_2023 VALUES LESS THAN('2023-04-01'),
    SUBPARTITION p1_q2_2023 VALUES LESS THAN('2023-07-01'),
    SUBPARTITION p1_q3_2023 VALUES LESS THAN('2023-10-01'),
    SUBPARTITION p1_q4_2023 VALUES LESS THAN('2024-01-01')
    ),
  PARTITION  p2(
    SUBPARTITION p2_q1_2023 VALUES LESS THAN('2023-04-01'),
    SUBPARTITION p2_q2_2023 VALUES LESS THAN('2023-07-01'),
    SUBPARTITION p2_q3_2023 VALUES LESS THAN('2023-10-01'),
    SUBPARTITION p2_q4_2023 VALUES LESS THAN('2024-01-01')
  )
);

Parent topic: Subpartitioning