PARTITIONS
The PARTITIONS
table provides information about partitioned tables.
USE INFORMATION_SCHEMA;
DESC partitions;
The output is as follows:
+-------------------------------+--------------+------+------+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------------------+--------------+------+------+---------+-------+
| TABLE_CATALOG | varchar(512) | YES | | NULL | |
| TABLE_SCHEMA | varchar(64) | YES | | NULL | |
| TABLE_NAME | varchar(64) | YES | | NULL | |
| PARTITION_NAME | varchar(64) | YES | | NULL | |
| SUBPARTITION_NAME | varchar(64) | YES | | NULL | |
| PARTITION_ORDINAL_POSITION | bigint(21) | YES | | NULL | |
| SUBPARTITION_ORDINAL_POSITION | bigint(21) | YES | | NULL | |
| PARTITION_METHOD | varchar(18) | YES | | NULL | |
| SUBPARTITION_METHOD | varchar(12) | YES | | NULL | |
| PARTITION_EXPRESSION | longtext | YES | | NULL | |
| SUBPARTITION_EXPRESSION | longtext | YES | | NULL | |
| PARTITION_DESCRIPTION | longtext | YES | | NULL | |
| TABLE_ROWS | bigint(21) | YES | | NULL | |
| AVG_ROW_LENGTH | bigint(21) | YES | | NULL | |
| DATA_LENGTH | bigint(21) | YES | | NULL | |
| MAX_DATA_LENGTH | bigint(21) | YES | | NULL | |
| INDEX_LENGTH | bigint(21) | YES | | NULL | |
| DATA_FREE | bigint(21) | YES | | NULL | |
| CREATE_TIME | datetime | YES | | NULL | |
| UPDATE_TIME | datetime | YES | | NULL | |
| CHECK_TIME | datetime | YES | | NULL | |
| CHECKSUM | bigint(21) | YES | | NULL | |
| PARTITION_COMMENT | varchar(80) | YES | | NULL | |
| NODEGROUP | varchar(12) | YES | | NULL | |
| TABLESPACE_NAME | varchar(64) | YES | | NULL | |
| TIDB_PARTITION_ID | bigint(21) | YES | | NULL | |
| TIDB_PLACEMENT_POLICY_NAME | varchar(64) | YES | | NULL | |
+-------------------------------+--------------+------+------+---------+-------+
27 rows in set (0.00 sec)
CREATE TABLE test.t1 (id INT NOT NULL PRIMARY KEY) PARTITION BY HASH (id) PARTITIONS 2;
SELECT * FROM PARTITIONS WHERE table_schema='test' AND table_name='t1'\G
The output is as follows:
*************************** 1. row ***************************
TABLE_CATALOG: def
TABLE_SCHEMA: test
TABLE_NAME: t1
PARTITION_NAME: p0
SUBPARTITION_NAME: NULL
PARTITION_ORDINAL_POSITION: 1
SUBPARTITION_ORDINAL_POSITION: NULL
PARTITION_METHOD: HASH
SUBPARTITION_METHOD: NULL
PARTITION_EXPRESSION: `id`
SUBPARTITION_EXPRESSION: NULL
PARTITION_DESCRIPTION:
TABLE_ROWS: 0
AVG_ROW_LENGTH: 0
DATA_LENGTH: 0
MAX_DATA_LENGTH: 0
INDEX_LENGTH: 0
DATA_FREE: 0
CREATE_TIME: 2022-12-14 06:09:33
UPDATE_TIME: NULL
CHECK_TIME: NULL
CHECKSUM: NULL
PARTITION_COMMENT:
NODEGROUP: NULL
TABLESPACE_NAME: NULL
TIDB_PARTITION_ID: 89
TIDB_PLACEMENT_POLICY_NAME: NULL
*************************** 2. row ***************************
TABLE_CATALOG: def
TABLE_SCHEMA: test
TABLE_NAME: t1
PARTITION_NAME: p1
SUBPARTITION_NAME: NULL
PARTITION_ORDINAL_POSITION: 2
SUBPARTITION_ORDINAL_POSITION: NULL
PARTITION_METHOD: HASH
SUBPARTITION_METHOD: NULL
PARTITION_EXPRESSION: `id`
SUBPARTITION_EXPRESSION: NULL
PARTITION_DESCRIPTION:
TABLE_ROWS: 0
AVG_ROW_LENGTH: 0
DATA_LENGTH: 0
MAX_DATA_LENGTH: 0
INDEX_LENGTH: 0
DATA_FREE: 0
CREATE_TIME: 2022-12-14 06:09:33
UPDATE_TIME: NULL
CHECK_TIME: NULL
CHECKSUM: NULL
PARTITION_COMMENT:
NODEGROUP: NULL
TABLESPACE_NAME: NULL
TIDB_PARTITION_ID: 90
TIDB_PLACEMENT_POLICY_NAME: NULL
2 rows in set (0.00 sec)