Migrating Data to GaussDB(for MySQL) Using mysqldump

Preparing for Data Migration

GaussDB(for MySQL) supports public accessibility. You can access GaussDB(for MySQL) through a private network or EIP.

  1. Prepare an ECS in the same VPC subnet as GaussDB(for MySQL) or prepare a device for accessing GaussDB(for MySQL) over a public network.
    • To connect to a DB instance through an ECS, you must first create an ECS.

      For details on how to create and log in to an ECS, see descriptions about creating an ECS and logging in an ECS in the Elastic Cloud Server User Guide.

    • To connect to a DB instance through an EIP, you must:
      1. Bind the EIP to the DB instance. For details, see Binding an EIP.
      2. Ensure that the local device can access the EIP that has been bound to the DB instance.
  2. Install the MySQL client on the prepared ECS or device.

    For details, see How Can I Install the MySQL Client?

    The version of the GaussDB(for MySQL) client must be the same as or later than that of the GaussDB(for MySQL) server. The MySQL database or client provides the mysqldump and mysql tools by default.

Exporting Data

Before migrating data to GaussDB(for MySQL), you need to export data first.

  • The export tool must match the DB engine version.
  • Database migration is performed offline. Before the migration, you must stop any applications using the source database.
  1. Log in to the prepared ECS or device that can access GaussDB(for MySQL) DB instances.
  2. Use the mysqldump tool to export metadata into an SQL file.

    MySQL databases are required for GaussDB(for MySQL) management. When exporting metadata, do not specify --all-database. Otherwise, the databases will be unavailable.

    mysqldump --databases <DB_NAME> --single-transaction --order-by-primary --hex-blob --no-data --routines --events --set-gtid-purged=OFF -u <DB_USER> -p -h <DB_ADDRESS> -P <DB_PORT> |sed -e 's/DEFINER[ ]*=[ ]*[^*]*\*/\*/' -e 's/DEFINER[ ]*=.*FUNCTION/FUNCTION/' -e 's/DEFINER[ ]*=.*PROCEDURE/PROCEDURE/' -e 's/DEFINER[ ]*=.*TRIGGER/TRIGGER/' -e 's/DEFINER[ ]*=.*EVENT/EVENT/' > <BACKUP_FILE>

    • DB_NAME indicates the name of the database to be migrated.
    • DB_USER indicates the database username.
    • DB_ADDRESS indicates the database address.
    • DB_PORT indicates the database port.
    • BACKUP_FILE indicates the name of the file to which the data will be exported.

    Enter the database password as prompted.

    Example:

    mysqldump --databases gaussdb --single-transaction --order-by-primary --hex-blob --no-data --routines --events --set-gtid-purged=OFF -u root -p -h 192.168.151.18 -P 3306 |sed -e 's/DEFINER[ ]*=[ ]*[^*]*\*/\*/' -e 's/DEFINER[ ]*=.*FUNCTION/FUNCTION/' -e 's/DEFINER[ ]*=.*PROCEDURE/PROCEDURE/' -e 's/DEFINER[ ]*=.*TRIGGER/TRIGGER/' -e 's/DEFINER[ ]*=.*EVENT/EVENT/' > dump-defs.sql

    Enter password:

    After this command is executed, the dump-defs.sql file will be generated.

  3. Use the mysqldump tool to export data into an SQL file.

    MySQL databases are required for GaussDB(for MySQL) management. When exporting metadata, do not specify --all-database. Otherwise, the databases will be unavailable.

    mysqldump --databases <DB_NAME> --single-transaction --hex-blob --set-gtid-purged=OFF --no-create-info --skip-triggers -u <DB_USER> -p -h <DB_ADDRESS> -P <DB_PORT> -r <BACKUP_FILE>

    For details on the parameters in the preceding command, see 2.

    Enter the database password as prompted.

    Example:

    mysqldump --databases gaussdb --single-transaction --hex-blob --set-gtid-purged=OFF --no-create-info --skip-triggers -u root -p -h 192.168.151.18 -P 3306 -r dump-data.sql

    After this command is executed, the dump-data.sql file will be generated.

Importing Data

You can use a client to connect to a GaussDB(for MySQL) DB instance through an ECS or a device and then import the exported SQL file into that DB instance.

If the source database contains triggers, storage processes, functions, or event invocation, you must set log_bin_trust_function_creators to ON for the destination database before importing data.

  1. Import metadata into GaussDB(for MySQL).

    Use the MySQL tool to connect to the GaussDB(for MySQL) DB instance, enter the password, and run the following command to import metadata:

    mysql -f -h <DB_ADDRESS> -P <DB_PORT> -u root -p < <BACKUP_DIR>/dump-defs.sql

    • DB_ADDRESS indicates the IP address of the GaussDB(for MySQL) DB instance.
    • DB_PORT indicates the GaussDB(for MySQL) DB instance port.
    • BACKUP_DIR indicates the directory where dump-defs.sql is stored.

    Example:

    mysql -f -h 172.16.66.198 -P 3306 -u root -p < dump-defs.sql

    Enter password:

  2. Import data into GaussDB(for MySQL).

    mysql -f -h <DB_ADDRESS> -P <DB_PORT> -u root -p < <BACKUP_DIR>/dump-data.sql

    • DB_ADDRESS indicates the IP address of the GaussDB(for MySQL) DB instance.
    • DB_PORT indicates the GaussDB(for MySQL) DB instance port.
    • BACKUP_DIR indicates the directory where dump-data.sql is stored.

    Example:

    mysql -f -h 172.16.66.198 -P 3306 -u root -p < dump-data.sql

    Enter password:

  3. View the import result.

    mysql> show databases;

    In this example, the database named my_db has been imported.

    mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| my_db              |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

Parent topic: Data Migration