The mapping wizards create a new target definition based on columns in the source definition and the options you select. This ensures the resulting target table contains the necessary columns for the mapping. By default, the resulting target definition has:

After a wizard creates a target definition for the mapping, use the Target Designer to create the target table in the target database before running the session.

If the repository and target database types differ, be sure to change the database type of the target definition to match the target database before generating the target.