TIFLASH_TABLES
TIFLASH_TABLES 表提供关于 TiFlash 中数据表的统计信息。
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)
TIFLASH_TABLES 表中的字段说明如下：
DATABASE: TiFlash 中所属表的数据库名。TABLE: TiFlash 中的表名。TIDB_DATABASE: TiDB 中所属表的数据库名。TIDB_TABLE: TiDB 中的表名。TABLE_ID: 表的内部 ID，在 TiDB 集群中唯一。IS_TOMBSTONE: 表示该表是否可以回收。1表示可以回收，0表示处于正常状态。SEGMENT_COUNT: 表中的段数。段是 TiFlash 中的数据管理单元。TOTAL_ROWS: 表中的总行数。TOTAL_SIZE: 表的总大小（字节数）。TOTAL_DELETE_RANGES: 表中的删除范围总数。DELTA_RATE_ROWS: Delta 层中表的总行数占比。DELTA_RATE_SEGMENTS: 表中包含非空 Delta 层的段的比例。DELTA_PLACED_RATE: 在 Delta 层中已完成索引构建的行的比例。DELTA_CACHE_SIZE: 表在 Delta 层中的缓存大小（字节）。DELTA_CACHE_RATE: Delta 层中缓存数据的占比。DELTA_CACHE_WASTED_RATE: Delta 层中无效缓存数据的占比。DELTA_INDEX_SIZE: Delta 层中索引占用的内存大小（字节）。AVG_SEGMENT_ROWS: 表所有段的平均行数。AVG_SEGMENT_SIZE: 表所有段的平均大小（字节）。DELTA_COUNT: 表中包含非空 Delta 层的段数。TOTAL_DELTA_ROWS: Delta 层中的总行数。TOTAL_DELTA_SIZE: Delta 层中数据的总大小（字节）。AVG_DELTA_ROWS: 所有 Delta 层中数据的平均行数。AVG_DELTA_SIZE: 所有 Delta 层中数据的平均大小（字节）。AVG_DELTA_DELETE_RANGES: 所有 Delta 层中删除范围操作的平均数。STABLE_COUNT: 表中包含非空 Stable 层的段数。TOTAL_STABLE_ROWS: 所有 Stable 层中的总行数。TOTAL_STABLE_SIZE: 所有 Stable 层中数据的总大小（字节）。TOTAL_STABLE_SIZE_ON_DISK: 所有 Stable 层中数据在磁盘上的占用空间（字节）。AVG_STABLE_ROWS: 所有 Stable 层中数据的平均行数。AVG_STABLE_SIZE: 所有 Stable 层中数据的平均大小（字节）。TOTAL_PACK_COUNT_IN_DELTA: 所有 Delta 层中列文件（Column Files）总数。MAX_PACK_COUNT_IN_DELTA: 单个 Delta 层中的最大列文件数。AVG_PACK_COUNT_IN_DELTA: 所有 Delta 层中列文件的平均数。AVG_PACK_ROWS_IN_DELTA: 所有 Delta 层中列文件的平均行数。AVG_PACK_SIZE_IN_DELTA: 所有 Delta 层中列文件的平均大小（字节）。TOTAL_PACK_COUNT_IN_STABLE: 所有 Stable 层中的 Pack 数量。AVG_PACK_COUNT_IN_STABLE: 所有 Stable 层中 Pack 的平均数。AVG_PACK_ROWS_IN_STABLE: 所有 Stable 层中 Pack 的平均行数。AVG_PACK_SIZE_IN_STABLE: Stable 层中 Pack 的平均大小（字节）。STORAGE_STABLE_NUM_SNAPSHOTS: Stable 层中的快照数。STORAGE_STABLE_OLDEST_SNAPSHOT_LIFETIME: Stable 层中最早快照的存活时间（秒）。STORAGE_STABLE_OLDEST_SNAPSHOT_THREAD_ID: 最早快照的线程 ID。STORAGE_STABLE_OLDEST_SNAPSHOT_TRACING_ID: 最早快照的追踪 ID。STORAGE_DELTA_NUM_SNAPSHOTS: Delta 层中的快照数。STORAGE_DELTA_OLDEST_SNAPSHOT_LIFETIME: Delta 层中最早快照的存活时间（秒）。STORAGE_DELTA_OLDEST_SNAPSHOT_THREAD_ID: 最早快照的线程 ID。STORAGE_DELTA_OLDEST_SNAPSHOT_TRACING_ID: 最早快照的追踪 ID。STORAGE_META_NUM_SNAPSHOTS: 元信息中的快照数。STORAGE_META_OLDEST_SNAPSHOT_LIFETIME: 元信息中最早快照的存活时间（秒）。STORAGE_META_OLDEST_SNAPSHOT_THREAD_ID: 元信息中最早快照的线程 ID。STORAGE_META_OLDEST_SNAPSHOT_TRACING_ID: 元信息中最早快照的追踪 ID。BACKGROUND_TASKS_LENGTH: 后台任务队列长度。TIFLASH_INSTANCE: TiFlash 实例的地址。