greatdb或mysql设置数据库的只读参数

show variables like '%read_only%';
+-----------------------+-------+
| Variable_name | Value |
+-----------------------+-------+
| innodb_read_only | OFF |
| read_only | OFF |
| super_read_only | OFF |
| transaction_read_only | OFF |
+-----------------------+-------+
4 rows in set (0.04 sec)

GreatDB Cluster[(none)]> set global read_only=1;

read_only=0 为关闭只读，可以写，对应value值为OFF；read_only=1 为只读,不可以写，对应value值为ON