title: Sqoop not able to map oracle column types to hive column
body: <p>I am sqooping a bunch of Oracle 10g tables in to hive. I am working on Hortonworks HDP2.3 on my cluster.
  One of the oracle table with more than 100 columns has a ROW_ID column, which I found out is of type oracle.sql.ROWID.
  Sqoop is throwing error :</p>
  
  <pre><code>2016-02-04 16:09:19,746 ERROR - [main:] ~ Cannot resolve SQL type -8 (ClassWriter:645)
  2016-02-04 16:09:19,747 ERROR - [main:] ~ Cannot resolve SQL type -8 (ClassWriter:645)
  2016-02-04 16:09:19,747 ERROR - [main:] ~ No Java type for SQL type -8 for column ROW_ID (ClassWriter:718)
  2016-02-04 16:09:19,748 ERROR - [main:] ~ No Java type for SQL type -8 for column ROW_ID (ClassWriter:718)
  2016-02-04 16:09:19,749 ERROR - [main:] ~ No Java type for SQL type -8 for column ROW_ID (ClassWriter:798)
  2016-02-04 16:09:19,756 ERROR - [main:] ~ Got exception running Sqoop: java.lang.NullPointerException (Sqoop:181)
  java.lang.NullPointerException
          at org.apache.sqoop.orm.ClassWriter.parseNullVal(ClassWriter.java:1377)
          at org.apache.sqoop.orm.ClassWriter.parseColumn(ClassWriter.java:1402)
          at org.apache.sqoop.orm.ClassWriter.myGenerateParser(ClassWriter.java:1528)
          at org.apache.sqoop.orm.ClassWriter.generateParser(ClassWriter.java:1491)
          at org.apache.sqoop.orm.ClassWriter.generateClassForColumns(ClassWriter.java:1920)
          at org.apache.sqoop.orm.ClassWriter.generate(ClassWriter.java:1736)
          at org.apache.sqoop.tool.CodeGenTool.generateORM(CodeGenTool.java:107)
          at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:478)
          at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:605)
          at org.apache.sqoop.Sqoop.run(Sqoop.java:143)
          at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
          at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:179)
          at org.apache.sqoop.Sqoop.runTool(Sqoop.java:218)
          at org.apache.sqoop.Sqoop.runTool(Sqoop.java:227)
          at org.apache.sqoop.Sqoop.main(Sqoop.java:236)
  </code></pre>
  
  <p>Is there a way to map this oracle column type to any hive column type or just make it string?</p>