sqoop从hive中导出oracle数据

1.从hive上导出数据到oracle时，报如下错误

执行语句：

sqoop export --connect jdbc:oracle:thin:@192.168.0.113:1521:cyanalyse --username xxxxxxx--password xxxxxx --table sms_count  --export-dir /user/hive/hivedata/user_count --input-fields-terminated-by '\001'

错误信息：

14/10/21 11:18:16 ERROR sqoop.Sqoop: Got exception running Sqoop: java.lang.IllegalArgumentException: Attempted to generate class with no columns!
java.lang.IllegalArgumentException: Attempted to generate class with no columns!

修改如下：

sqoop export --connect jdbc:oracle:thin:@192.168.0.113:1521:cyanalyse --username xxxxxxx--password xxxxxx --table sms_count --columns userid,sms_count --export-dir /user/hive/hivedata/user_count --input-fields-terminated-by '\001'

修改后能正确执行。