This is solved. Used Writable instead of LongWritable or NullWritable in Mapper input key type.
Thanks Suraj Nayak On 19-Mar-2015 9:48 PM, "Suraj Nayak" <snay...@gmail.com> wrote: > Is this related to https://issues.apache.org/jira/browse/HIVE-4329 ? Is > there a workaround? > > On Thu, Mar 19, 2015 at 9:47 PM, Suraj Nayak <snay...@gmail.com> wrote: > >> Hi All, >> >> I was successfully able to integrate HCatMultipleInputs with the patch >> for the tables created with TEXTFILE. But I get error when I read table >> created with ORC file. The error is below : >> >> 15/03/19 10:51:32 INFO mapreduce.Job: Task Id : >> attempt_1425012118520_9756_m_000000_0, Status : FAILED >> Error: java.lang.ClassCastException: org.apache.hadoop.io.NullWritable >> cannot be cast to org.apache.hadoop.io.LongWritable >> at com.abccompany.mapreduce.MyMapper.map(MyMapper.java:15) >> at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:145) >> at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764) >> at org.apache.hadoop.mapred.MapTask.run(MapTask.java:340) >> at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:167) >> at java.security.AccessController.doPrivileged(Native Method) >> at javax.security.auth.Subject.doAs(Subject.java:415) >> at >> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1557) >> at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:162) >> >> >> Can anyone help? >> >> Thanks in advance! >> >> On Wed, Mar 18, 2015 at 11:00 PM, Suraj Nayak <snay...@gmail.com> wrote: >> >>> Hi All, >>> >>> https://issues.apache.org/jira/browse/HIVE-4997 patch helped! >>> >>> >>> On Tue, Mar 17, 2015 at 1:05 AM, Suraj Nayak <snay...@gmail.com> wrote: >>> >>>> Hi, >>>> >>>> I tried reading data via HCatalog for 1 Hive table in MapReduce using >>>> something similar to >>>> https://cwiki.apache.org/confluence/display/Hive/HCatalog+InputOutput#HCatalogInputOutput-RunningMapReducewithHCatalog. >>>> I was able to read successfully. >>>> >>>> Now am trying to read 2 tables, as the requirement is to join 2 tables. >>>> I did not find API similar to *FileInputFormat.addInputPaths* in >>>> *HCatInputFormat*. What is the equivalent of the same in HCat ? >>>> >>>> I had performed join using FilesInputFormat in HDFS(by getting split >>>> information in mapper). This article( >>>> http://www.codingjunkie.com/mapreduce-reduce-joins) helped me code >>>> join. <http://www.codingjunkie.com/mapreduce-reduce-joins/> Can >>>> someone suggest how I can perform join operation using HCatalog ? >>>> >>>> Briefly, the aim is to >>>> >>>> - Read 2 tables (almost similar schema) >>>> - If key exists in both the table send it to same reducer. >>>> - Do some processing on the records in reducer. >>>> - Save the output into file/Hive table. >>>> >>>> *P.S : The reason for using MapReduce to perform join is because of >>>> complex requirement which can't be solved via Hive/Pig directly. * >>>> >>>> Any help will be greatly appreciated :) >>>> >>>> -- >>>> Thanks >>>> Suraj Nayak M >>>> >>> >>> >>> >>> -- >>> Thanks >>> Suraj Nayak M >>> >> >> >> >> -- >> Thanks >> Suraj Nayak M >> > > > > -- > Thanks > Suraj Nayak M >
