When connecting to an Oracle database, the Sqoop import
command
requires case-sensitive table names and usernames (typically uppercase). Otherwise
the import fails with error message "Attempted to generate class with no
columns!"
Prior to the resolution of SQOOP-741,
import-all-tables
would fail for an Oracle database. See the
JIRA for more information.
The import-all-tables
command has additional restrictions. See
Chapter 8 in the Sqoop User
Guide.