[SQOOP-2945] Oracle CLOB mapped to String is unable to import the data (SQLException in nextKeyValue)

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.4.6
• Fix Version/s: 1.5.0
• Component/s: connectors/oracle
• Assignee: Unassigned
• Reporter: Senthil Ganesh
• Created: 03/Jun/16 07:50
• Updated: 30/Oct/17 14:09

Description

If we map any CLOB column from Oracle to String with "--map-column-java CLOB_COL=String" during Sqoop import, we are hitting below exception:

...
map 0% reduce 0%
map 50% reduce 0%
Task Id : attempt_1462336475649_1097_m_000000_0, Status : FAILED
Error: java.io.IOException: SQLException in nextKeyValue
at org.apache.sqoop.mapreduce.db.DBRecordReader.nextKeyValue(DBRecordReader.java:277)
at org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.nextKeyValue(MapTask.java:556)
at org.apache.hadoop.mapreduce.task.MapContextImpl.nextKeyValue(MapContextImpl.java:80)
at org.apache.hadoop.mapreduce.lib.map.WrappedMapper$Context.nextKeyValue(WrappedMapper.java:91)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)
at org.apache.sqoop.mapreduce.AutoProgressMapper.run(AutoProgressMapper.java:64)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:163)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1671)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
...

As we like to store the result in Hive (which do not support CLOB), we need to map this column to String.