java.io.IOException: Cannot join values on null key. Did you specify a key column that exists?

Stack Overflow | Mahesh | 5 months ago
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    Sqoop merge issue - Hortonworks

    Stack Overflow | 5 months ago | Mahesh
    java.io.IOException: Cannot join values on null key. Did you specify a key column that exists?

    Root Cause Analysis

    1. java.io.IOException

      Cannot join values on null key. Did you specify a key column that exists?

      at org.apache.sqoop.mapreduce.MergeMapperBase.processRecord()
    2. org.apache.sqoop
      MergeTextMapper.map
      1. org.apache.sqoop.mapreduce.MergeMapperBase.processRecord(MergeMapperBase.java:79)
      2. org.apache.sqoop.mapreduce.MergeTextMapper.map(MergeTextMapper.java:58)
      3. org.apache.sqoop.mapreduce.MergeTextMapper.map(MergeTextMapper.java:34)
      3 frames
    3. Hadoop
      YarnChild$2.run
      1. org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
      2. org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
      3. org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
      4. org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:168)
      4 frames
    4. Java RT
      Subject.doAs
      1. java.security.AccessController.doPrivileged(Native Method)
      2. javax.security.auth.Subject.doAs(Subject.java:422)
      2 frames
    5. Hadoop
      UserGroupInformation.doAs
      1. org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
      1 frame
    6. Hadoop
      YarnChild.main
      1. org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:162)
      1 frame