| title | summary |
|---|---|
TIFLASH_TABLES |
Learn the `TIFLASH_TABLES` information_schema table. |
Warning:
Do not use this table in production environments, as the fields of the table are unstable, and subject to change in new releases of TiDB, without prior notice.
Note:
This table is not available on TiDB Serverless clusters.
The TIFLASH_TABLES table provides statistical information about data tables in TiFlash.
USE information_schema;
DESC tiflash_tables;+-------------------------------------------+--------------+------+------+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------------------------------+--------------+------+------+---------+-------+
| DATABASE | varchar(64) | YES | | NULL | |
| TABLE | varchar(64) | YES | | NULL | |
| TIDB_DATABASE | varchar(64) | YES | | NULL | |
| TIDB_TABLE | varchar(64) | YES | | NULL | |
| TABLE_ID | bigint(64) | YES | | NULL | |
| IS_TOMBSTONE | bigint(64) | YES | | NULL | |
| SEGMENT_COUNT | bigint(64) | YES | | NULL | |
| TOTAL_ROWS | bigint(64) | YES | | NULL | |
| TOTAL_SIZE | bigint(64) | YES | | NULL | |
| TOTAL_DELETE_RANGES | bigint(64) | YES | | NULL | |
| DELTA_RATE_ROWS | double | YES | | NULL | |
| DELTA_RATE_SEGMENTS | double | YES | | NULL | |
| DELTA_PLACED_RATE | double | YES | | NULL | |
| DELTA_CACHE_SIZE | bigint(64) | YES | | NULL | |
| DELTA_CACHE_RATE | double | YES | | NULL | |
| DELTA_CACHE_WASTED_RATE | double | YES | | NULL | |
| DELTA_INDEX_SIZE | bigint(64) | YES | | NULL | |
| AVG_SEGMENT_ROWS | double | YES | | NULL | |
| AVG_SEGMENT_SIZE | double | YES | | NULL | |
| DELTA_COUNT | bigint(64) | YES | | NULL | |
| TOTAL_DELTA_ROWS | bigint(64) | YES | | NULL | |
| TOTAL_DELTA_SIZE | bigint(64) | YES | | NULL | |
| AVG_DELTA_ROWS | double | YES | | NULL | |
| AVG_DELTA_SIZE | double | YES | | NULL | |
| AVG_DELTA_DELETE_RANGES | double | YES | | NULL | |
| STABLE_COUNT | bigint(64) | YES | | NULL | |
| TOTAL_STABLE_ROWS | bigint(64) | YES | | NULL | |
| TOTAL_STABLE_SIZE | bigint(64) | YES | | NULL | |
| TOTAL_STABLE_SIZE_ON_DISK | bigint(64) | YES | | NULL | |
| AVG_STABLE_ROWS | double | YES | | NULL | |
| AVG_STABLE_SIZE | double | YES | | NULL | |
| TOTAL_PACK_COUNT_IN_DELTA | bigint(64) | YES | | NULL | |
| MAX_PACK_COUNT_IN_DELTA | bigint(64) | YES | | NULL | |
| AVG_PACK_COUNT_IN_DELTA | double | YES | | NULL | |
| AVG_PACK_ROWS_IN_DELTA | double | YES | | NULL | |
| AVG_PACK_SIZE_IN_DELTA | double | YES | | NULL | |
| TOTAL_PACK_COUNT_IN_STABLE | bigint(64) | YES | | NULL | |
| AVG_PACK_COUNT_IN_STABLE | double | YES | | NULL | |
| AVG_PACK_ROWS_IN_STABLE | double | YES | | NULL | |
| AVG_PACK_SIZE_IN_STABLE | double | YES | | NULL | |
| STORAGE_STABLE_NUM_SNAPSHOTS | bigint(64) | YES | | NULL | |
| STORAGE_STABLE_OLDEST_SNAPSHOT_LIFETIME | double | YES | | NULL | |
| STORAGE_STABLE_OLDEST_SNAPSHOT_THREAD_ID | bigint(64) | YES | | NULL | |
| STORAGE_STABLE_OLDEST_SNAPSHOT_TRACING_ID | varchar(128) | YES | | NULL | |
| STORAGE_DELTA_NUM_SNAPSHOTS | bigint(64) | YES | | NULL | |
| STORAGE_DELTA_OLDEST_SNAPSHOT_LIFETIME | double | YES | | NULL | |
| STORAGE_DELTA_OLDEST_SNAPSHOT_THREAD_ID | bigint(64) | YES | | NULL | |
| STORAGE_DELTA_OLDEST_SNAPSHOT_TRACING_ID | varchar(128) | YES | | NULL | |
| STORAGE_META_NUM_SNAPSHOTS | bigint(64) | YES | | NULL | |
| STORAGE_META_OLDEST_SNAPSHOT_LIFETIME | double | YES | | NULL | |
| STORAGE_META_OLDEST_SNAPSHOT_THREAD_ID | bigint(64) | YES | | NULL | |
| STORAGE_META_OLDEST_SNAPSHOT_TRACING_ID | varchar(128) | YES | | NULL | |
| BACKGROUND_TASKS_LENGTH | bigint(64) | YES | | NULL | |
| TIFLASH_INSTANCE | varchar(64) | YES | | NULL | |
+-------------------------------------------+--------------+------+------+---------+-------+
54 rows in set (0.00 sec)Fields in the TIFLASH_TABLES table are described as follows:
DATABASE: The name of the database that the table belongs to in TiFlash.TABLE: The name of the table in TiFlash.TIDB_DATABASE: The name of the database that the table belongs to in TiDB.TIDB_TABLE: The name of the table in TiDB.TABLE_ID: The internal ID of the table, which is unique within a TiDB cluster.IS_TOMBSTONE: Indicates whether the table can be recycled.1indicates that the table can be recycled, and0indicates that the table is in a normal state.SEGMENT_COUNT: The number of segments in the table. A segment is a data management unit in TiFlash.TOTAL_ROWS: The total number of rows in the table.TOTAL_SIZE: The total size of the table (in bytes).TOTAL_DELETE_RANGES: The total number of Delete Ranges in the table.DELTA_RATE_ROWS: The ratio of the total rows of the table in the Delta layer to the total rows of that table.DELTA_RATE_SEGMENTS: The proportion of segments that contain a non-empty Delta layer in the table.DELTA_PLACED_RATE: The proportion of rows that have completed index construction of the table in the Delta layer.DELTA_CACHE_SIZE: The size of the cache of the table in the Delta layer (in bytes).DELTA_CACHE_RATE: The proportion of cache data of the table in the Delta layer.DELTA_CACHE_WASTED_RATE: The proportion of invalid cache data of the table in the Delta layer.DELTA_INDEX_SIZE: The size of the memory occupied by indexes in the Delta layer (in bytes).AVG_SEGMENT_ROWS: The average number of rows in all segments of the table.AVG_SEGMENT_SIZE: The average size of all segments of the table (in bytes).DELTA_COUNT: The number of segments that contain a non-empty Delta layer in the table.TOTAL_DELTA_ROWS: The total number of rows in the Delta layer.TOTAL_DELTA_SIZE: The total size of the data in the Delta layer (in bytes).AVG_DELTA_ROWS: The average number of rows of data in all Delta layers.AVG_DELTA_SIZE: The average size of data in all Delta layers (in bytes).AVG_DELTA_DELETE_RANGES: The average number of Delete Range operations in all Delta layers.STABLE_COUNT: The number of segments that contain a non-empty Stable layer in the table.TOTAL_STABLE_ROWS: The total number of rows in all Stable layers.TOTAL_STABLE_SIZE: The total size of the data in all Stable layers (in bytes).TOTAL_STABLE_SIZE_ON_DISK: The disk space occupied by the data in all Stable layers (in bytes).AVG_STABLE_ROWS: The average number of rows of data in all Stable layers.AVG_STABLE_SIZE: The average size of data in all Stable layers (in bytes).TOTAL_PACK_COUNT_IN_DELTA: The total number of Column Files in all Delta layers.MAX_PACK_COUNT_IN_DELTA: The maximum number of Column Files in a single Delta layer.AVG_PACK_COUNT_IN_DELTA: The average number of Column Files in all Delta layers.AVG_PACK_ROWS_IN_DELTA: The average number of rows in all Column Files in all Delta layers.AVG_PACK_SIZE_IN_DELTA: The average size of data in all Column Files in all Delta layers (in bytes).TOTAL_PACK_COUNT_IN_STABLE: The total number of Packs in all Stable layers.AVG_PACK_COUNT_IN_STABLE: The average number of Packs in all Stable layers.AVG_PACK_ROWS_IN_STABLE: The average number of rows in all Packs in all Stable layers.AVG_PACK_SIZE_IN_STABLE: The average size of data in all Packs in the Stable layer (in bytes).STORAGE_STABLE_NUM_SNAPSHOTS: The number of snapshots in the Stable layer.STORAGE_STABLE_OLDEST_SNAPSHOT_LIFETIME: The duration of the earliest snapshot in the Stable layer (in seconds).STORAGE_STABLE_OLDEST_SNAPSHOT_THREAD_ID: The thread ID of the earliest snapshot in the Stable layer.STORAGE_STABLE_OLDEST_SNAPSHOT_TRACING_ID: The tracing ID of the earliest snapshot in the Stable layer.STORAGE_DELTA_NUM_SNAPSHOTS: The number of snapshots in the Delta layer.STORAGE_DELTA_OLDEST_SNAPSHOT_LIFETIME: The duration of the earliest snapshot in the Delta layer (in seconds).STORAGE_DELTA_OLDEST_SNAPSHOT_THREAD_ID: The thread ID of the earliest snapshot in the Delta layer.STORAGE_DELTA_OLDEST_SNAPSHOT_TRACING_ID: The tracing ID of the earliest snapshot in the Delta layer.STORAGE_META_NUM_SNAPSHOTS: The number of snapshots in the meta information.STORAGE_META_OLDEST_SNAPSHOT_LIFETIME: The duration of the earliest snapshot in the meta information (in seconds).STORAGE_META_OLDEST_SNAPSHOT_THREAD_ID: The thread ID of the earliest snapshot in the meta information.STORAGE_META_OLDEST_SNAPSHOT_TRACING_ID: The tracing ID of the earliest snapshot in the meta information.BACKGROUND_TASKS_LENGTH: The length of the task queue in the background.TIFLASH_INSTANCE: The address of the TiFlash instance.