Before data migration, Data Transmission Service (DTS) checks whether a database with the same name as the source database exists in the target database system. If no such a database exists in the target instance, DTS creates a database. If the automatic creation fails, the precheck fails.

In the following cases, DTS cannot automatically create a database in the target instance and the precheck fails.

The name or character set of the source database do not comply with rules in the target RDS instance.

  • The name of the source database contains special characters other than underscores (_) and hyphens (-).
  • The character set of the source database is not UTF-8, GBK, Latin1, or UTF-8 (MB4).

Solution:

  1. Create a database in the target RDS instance that complies with the naming convention and character set rules. For more information, see Create a database for an RDS for MySQL instance.
    Note When you create the database, you must grant permissions to the target database account that is used by the data migration task.
  2. Log on to the DTS console.
  3. In the left-side navigation pane, click Data Migration.
  4. Find the data migration task and click Edit Task.Modify task configurations
  5. Click Set Whitelist and Next in the lower-right corner of the page.
  6. Configure the name of the target database by using the object name mapping feature. For more information about how to use this feature, see Object name mapping.
  7. Click Precheck.

The permissions granted to the target database account are insufficient

Solution:

  1. Grant read and write permissions to the target database account. For more information about how to change permissions, see Modify the permissions of a standard account for an ApsaraDB RDS for MySQL instance
  2. Perform another precheck