RANGE COLUMNS and LIST COLUMNS Partitioning Types

RANGE COLUMNS and LIST COLUMNS are variants of, respectively, RANGE and LIST. With these partitioning types there is not a single partitioning expression; instead, a list of one or more columns is accepted. The following rules apply:

  • The list can contain one or more columns.
  • Columns can be of any integer, string, DATE, and DATETIME types.
  • Only bare columns are permitted; no expressions.

All the specified columns are compared to the specified values to determine which partition should contain a specific row. See below for details.

Syntax

The last part of a CREATE TABLE statement can be definition of the new table's partitions. In the case of RANGE COLUMNS partitioning, the syntax is the following:

PARTITION BY RANGE COLUMNS (col1, col2, ...)
(
	PARTITION partition_name VALUES LESS THAN (value1, value2, ...),
	[ PARTITION partition_name VALUES LESS THAN (value1, value2, ...), ... ]
)

The syntax for LIST COLUMNS is the following:

PARTITION BY LIST COLUMNS (partitioning_expression)
(
	PARTITION partition_name VALUES IN (value1, value2, ...),
	[ PARTITION partition_name VALUES IN (value1, value2, ...), ... ]
        [ PARTITION partititon_name DEFAULT ]
)

partition_name is the name of a partition.

Comparisons

To determine which partition should contain a row, all specified columns will be compared to each partition definition.

With LIST COLUMNS, a row matches a partition if all row values are identical to the specified values. At most one partition can match the row.

With RANGE COLUMNS, a row matches a partition if all row values are less than specified values. The first partition that matches row values will be used.

DEFAULT partition catch all records which do not fit in other partitions. Only one DEFAULT partititon allowed. This option added in MariaDB 10.2.

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