SHOW SINGLE TABLE (tableRule | RULES) [FROM schemaName]
SHOW SINGLE TABLES 
tableRule:
    RULE tableName
| 列 | 说明 | 
|---|---|
| name | 规则名称 | 
| resource_name | 数据源名称 | 
| 列 | 说明 | 
|---|---|
| table_name | 单表名称 | 
| resource_name | 单表所在的数据源名称 | 
single table rules
sql> show single table rules;
+---------+---------------+
| name    | resource_name |
+---------+---------------+
| default | ds_1          |
+---------+---------------+
1 row in set (0.01 sec)
single tables
mysql> show single tables;
+--------------+---------------+
| table_name   | resource_name |
+--------------+---------------+
| t_single_0   | ds_0          |
| t_single_1   | ds_1          |
+--------------+---------------+
2 rows in set (0.02 sec)
