What Risky Operations on RDS for MySQL Will Affect DDM?

Table 1 lists risky operations on RDS for MySQL.

**Table 1** Risky operations on RDS for MySQL
Operation Type	Operation	Impact of the Operation
Operations on the RDS console	Deleting an RDS MySQL DB instance	After an RDS MySQL DB instance is deleted, all schemas and logical tables of the DDM instance associated with the DB instance become unavailable.
	Performing the primary/standby switchover of an RDS MySQL DB instance	RDS may be intermittently interrupted during the primary/standby switchover. In addition, a small amount of data may be lost in case of long delay in primary/standby synchronization. Creating schemas or logical tables or scaling out schemas is not allowed on DDM during the primary/standby switchover of the RDS MySQL DB instance. After a primary/standby switchover of an RDS MySQL instance, the RDS MySQL instance ID in DDM remains unchanged.
	Restarting an RDS MySQL DB instance	An RDS MySQL DB instance being restarted is unavailable, and the DDM service will be affected.
	Resetting a password	After the RDS DB instance password is reset, enter the new password on DDM when creating a schema.
	Modifying a parameter template	The following parameters are set to fixed values. If their values are changed, DDM will not function properly. lower_case_table_names: Set this parameter to 1, indicating that data table names and sequence names are case-insensitive. local_infile: Set this parameter to ON in scale-out scenarios.
	Modifying a security group	The DDM instance cannot connect to the RDS MySQL DB instance.
	Modifying a VPC	The DDM instance and RDS MySQL DB instance cannot communicate with each other if they are in different VPCs.
	Restoring data	Restoring data may damage data integrity.
Operations through an RDS MySQL client	Deleting a physical database created on DDM	After a physical database is deleted, the original data will be lost and new data cannot be written into the database.
	Deleting a physical account created on DDM	After a physical account is deleted, logical tables cannot be created on DDM.
	Deleting a physical table created on DDM	After a logical table is deleted, data will be lost on DDM, and the table cannot be used on DDM.
	Modifying the name of a logical table created on DDM	After the name of a logical table is modified, DDM cannot obtain the table data, and the table cannot be used on DDM.
	Changing a record	Changing a record in a broadcast table will affect the data consistency of shards.
	Modifying a whitelist	The DDM instance cannot access the RDS MySQL DB instance if the DDM instance is not in the DB instance whitelist.