查询已存在 TiFlash 中的表
mysql :(none)> SELECT * FROM INFORMATION_SCHEMA.TIFLASH_REPLICA;
+--------------+-------------------------------+----------+---------------+-----------------+-----------+----------+
| TABLE_SCHEMA | TABLE_NAME                    | TABLE_ID | REPLICA_COUNT | LOCATION_LABELS | AVAILABLE | PROGRESS |
+--------------+-------------------------------+----------+---------------+-----------------+-----------+----------+
| dev2_pfizer  | dc_flowdata_deliver_inventory | 10761    | 1             |                 | 1         | 1.0      |
| dev2_pfizer  | dc_flowdata_deliver_purchase  | 11241    | 1             |                 | 1         | 1.0      |
| dev2_pfizer  | dc_flowdata_deliver_sale      | 11539    | 1             |                 | 1         | 1.0      |
| leojiang     | test1                         | 13095    | 1             |                 | 1         | 1.0      |
+--------------+-------------------------------+----------+---------------+-----------------+-----------+----------+

4 rows in set
Time: 0.016s
mysql :(none)>

TiFlash 创建/删除

ALTER TABLE 表名 SET TIFLASH REPLICA 副本数;
ALTER TABLE 表名 SET TIFLASH REPLICA 0;

-- 将TiKV中的表加入到 TiFlash
ALTER TABLE table_1 SET TIFLASH REPLICA 1;

-- 删除TiFlash副本
ALTER TABLE table_1 SET TIFLASH REPLICA 0;

使用注解,手动指定SQL句,从哪个存储引擎读取数据[TiKV|TiFlash]

SELECT /*+ read_from_storage(tikv[表名] )*/ COUNT(*) FROM 表名;
SELECT /*+ read_from_storage(tiflash[表名] )*/ COUNT(*) FROM 表名;

-- 手动指定 SQL句 从 TiKV 中读取数据
SELECT /*+ read_from_storage(tikv[table_1] )*/ COUNT(*) FROM table_1;

-- 手动指定 SQL句 从 tiflash 中读取数据
SELECT /*+ read_from_storage(tiflash[table_1] )*/ COUNT(*) FROM table_1;

分类: TiDB

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