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RANGE COLUMNS and LIST COLUMNS Partitioning Types

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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 or sting type, as well as DATE and DATETIME.
  • 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_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.

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