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Information Schema PARTITIONS Table

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. 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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https://mariadb.com/kb/en/information-schema-partitions-table/