Information Schema PARTITIONS Table

The Information Schema PARTITIONS table provides detailed metadata about table partitions, including partition methods and data distribution.

The Information Schema PARTITIONS contains information about table partitions, with each record corresponding to a single partition or subpartition of a partitioned table. Each non-partitioned table also has a record in the PARTITIONS table, but most of the values are NULL.

It contains the following columns:

Column	Description
TABLE_CATALOG	Always def.
TABLE_SCHEMA	Database name.
TABLE_NAME	Table name containing the partition.
PARTITION_NAME	Partition name.
SUBPARTITION_NAME	Subpartition name, or NULL if not a subpartition.
PARTITION_ORDINAL_POSITION	Order of the partition starting from 1.
SUBPARTITION_ORDINAL_POSITION	Order of the subpartition starting from 1.
PARTITION_METHOD	The partitioning type; one of RANGE, LIST, HASH, LINEAR HASH, KEY or LINEAR KEY.
SUBPARTITION_METHOD	Subpartition type; one of HASH, LINEAR HASH, KEY or LINEAR KEY, or NULL if not a subpartition.
PARTITION_EXPRESSION	Expression used to create the partition by the CREATE TABLE or ALTER TABLE statement.
SUBPARTITION_EXPRESSION	Expression used to create the subpartition by the CREATE TABLE or ALTER TABLE statement, or NULL if not a subpartition.
PARTITION_DESCRIPTION	For a RANGE partition, contains either MAXINTEGER or an integer, as set in the VALUES LESS THAN clause. For a LIST partition, contains a comma-separated list of integers, as set in the VALUES IN. For a SYSTEM_TIME INTERVAL partition, shows a defined upper boundary timestamp for historical values (the last history partition can contain values above the upper boundary). NULL if another type of partition.
TABLE_ROWS	Number of rows in the table (may be an estimate for some storage engines).
AVG_ROW_LENGTH	Average row length, that is DATA_LENGTH divided by TABLE_ROWS
DATA_LENGTH	Total number of bytes stored in all rows of the partition.
MAX_DATA_LENGTH	Maximum bytes that could be stored in the partition.
INDEX_LENGTH	Size in bytes of the partition index file.
DATA_FREE	Unused bytes allocated to the partition.
CREATE_TIME	Time the partition was created
UPDATE_TIME	Time the partition was last modified.
CHECK_TIME	Time the partition was last checked, or NULL for storage engines that don't record this information.
CHECKSUM	Checksum value, or NULL if none.
PARTITION_COMMENT	Partition comment, truncated to 80 characters, or an empty string if no comment.
NODEGROUP	Node group, only used for MySQL Cluster, defaults to 0.
TABLESPACE_NAME	Always default.

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