This topic describes how to migrate data from a self-managed MySQL instance to an ApsaraDB RDS for MySQL instance by using the mysqldump extension. The mysqldump extension is easy to use but causes long downtime. The mysqldump extension is suitable for scenarios in which the data volume is small or long downtime does not have a negative impact on your business.
Prerequisites
IP address whitelists are configured, a public endpoint is obtained, and databases and accounts are created for the RDS instance. For more information, see General workflow to use ApsaraDB RDS for MySQL.
Background information
ApsaraDB RDS for MySQL is fully compatible with open source MySQL. The process of migrating data from a self-managed MySQL instance to an RDS instance is similar to the process of migrating data from one MySQL server to another MySQL server.
Data Transmission Service (DTS) allows you to migrate data in a more convenient and efficient manner without service interruptions. We recommend that you use DTS to migrate data. For more information, see Overview of data migration methods.
For more information about the parameters of the mysqldump extension, see official MySQL documentation.
Scenarios
You want to migrate data from a self-managed MySQL instance to an ApsaraDB RDS for MySQL instance.
Usage notes
After the migration is complete, the names of all tables that are migrated from the self-managed MySQL instance are in lowercase on the RDS instance. You can use one of the following methods to check the case-sensitivity of table names for the ApsaraDB RDS for MySQL instance:
When you create an ApsaraDB RDS for MySQL instance, set the Table Name Case Sensitivity parameter to Case-sensitive. For more information, see Create an ApsaraDB RDS for MySQL instance.
If you want to enable the case-sensitivity of table names for an existing RDS instance, set the lower_case_table_names parameter to 0 in the ApsaraDB RDS console. For more information, see Modify the parameters of an ApsaraDB RDS for MySQL instance.
WarningAfter you set the lower_case_table_names parameter to 0, do not change the value to 1. If you change the value of this parameter to 1, the
ERROR 1146 (42S02): Table doesn't exist
error may be reported, and your workloads may be seriously affected.If your RDS instance runs MySQL 8.0, you cannot reconfigure the lower_case_table_names parameter for your RDS instance.
Procedure
Use the mysqldump extension to export the data, stored procedures, triggers, and functions of the self-managed MySQL instance.
ImportantWhen the export task is in progress, do not update the data. Wait until the export task is completed.
The user that is mentioned in the following steps must have the required permissions. For more information, see official MySQL documentation.
In the Linux CLI, run the following command to export the data as a file:
mysqldump -h 127.0.0.1 -u user -p --opt --default-character-set=utf8 --hex-blob <Name of the self-managed MySQL instance> --skip-triggers --skip-lock-tables > /tmp/<Name of the self-managed MySQL instance>.sql
Example
mysqldump -h 127.0.0.1 -u user -p --opt --default-character-set=utf8 --hex-blob testdb --skip-triggers --skip-lock-tables > /tmp/testdb.sql
In the Linux CLI, run the following command to export the stored procedures, triggers, and functions as a file:
mysqldump -h 127.0.0.1 -u user -p --opt --default-character-set=utf8 --hex-blob <Name of the self-managed MySQL instance> -R | sed -e 's/DEFINER[ ]*=[ ]*[^*]*\*/*/' > /tmp/<Name of the self-managed MySQL instance> Trigger.sql
Example
mysqldump -h 127.0.0.1 -u user -p --opt --default-character-set=utf8 --hex-blob testdb -R | sed -e 's/DEFINER[ ]*=[ ]*[^*]*\*/\*/' > /tmp/testdbTrigger.sql
NoteIf the self-managed MySQL instance does not contain stored procedures, triggers, or functions, you can skip this step.
Upload the exported files to a specified directory on an Elastic Compute Service (ECS) instance. In this example, the directory is /tmp.
NoteIf the self-managed MySQL instance resides on an ECS instance, you can skip this step.
Run the following commands to import the exported files into the RDS instance:
mysql -h <Endpoint of the RDS instance> -P <Port of the RDS instance> -u <RDS instance account> -p <Name of the RDS instance> < /tmp/<Name of the self-managed MySQL instance>.sql mysql -h <Endpoint of the RDS instance> -P <Port of the RDS instance > -u <RDS instance account> -p <Name of the RDS instance> < /tmp/<Name of the self-managed MySQL instance> Trigger.sql
NoteThe destination database on the RDS instance must be an existing database that you created. For more information about how to create a database, see Create a database.
The account that is used to log on to the RDS instance must be a privileged account or a standard account that has the read and write permissions.
Example
mysql -h rm-bpxxxxx.mysql.rds.aliyuncs.com -P 3306 -u testuser -p testdb < /tmp/testdb.sql mysql -h rm-bpxxxxx.mysql.rds.aliyuncs.com -P 3306 -u testuser -p testdb < /tmp/testdbTrigger.sql
After the import is complete, log on to the RDS instance and check whether the data is normal. For more information, see Use DMS to log on to an ApsaraDB RDS for MySQL instance.