Check Details
When migrating the source database to the target instance, ensure that there are no databases with the same name as the source database to be migrated in the target instance; otherwise, an error will be reported with the error details: "Check if the target database exists.".
Fixing Method
If a target database existence check error is reported: "Check if the target database exists," it means that the database to be migrated already exists in the target instance. Please delete or rename the database with the same name in the target instance and then retry.