A related question: may I have multiple tables as output, in a single Map Job? I understand that this is achievable by running multiple MR jobs, each with a different output table specified in the reduce class. What I want is to scan a source table once and generate multiple tables at one time. Thanks,
Best Regards, Wei Wei Tan Research Staff Member IBM T. J. Watson Research Center 19 Skyline Dr, Hawthorne, NY 10532 [email protected]; 914-784-6752 From: "Amlan Roy" <[email protected]> To: <[email protected]>, Date: 08/06/2012 09:05 AM Subject: RE: HBase MapReduce - Using mutiple tables as source Hi, If TableMapper and TableMapReduceUtil.initTableMapperJob() does not support multiple tables as input, can I use Hadoop Mapper/Reducer classes and specify the the input/output format myself? What I want to do is, I want to read two tables in the map phase and want to reduce them together. What is the best solution available in 0.92.0 (I understand the best solution is coming in version 0.96.0). Regards, Amlan -----Original Message----- From: Ioakim Perros [mailto:[email protected]] Sent: Monday, August 06, 2012 5:11 PM To: [email protected] Subject: Re: HBase MapReduce - Using mutiple tables as source Hi, Isn't that the case that you can always initiate a scanner inside a map job (referring to another table from which had been set into the configuration of TableMapReduceUtil.initTableMapperJob(...) ) ? Hope this serves as temporary solution. On 08/06/2012 02:35 PM, Mohammad Tariq wrote: > Hello Amlan, > > Issue is still unresolved...Will get fixed in 0.96.0. > > Regards, > Mohammad Tariq > > > On Mon, Aug 6, 2012 at 5:01 PM, Amlan Roy <[email protected]> wrote: >> Hi, >> >> >> >> While writing a MapReduce job for HBase, can I use multiple tables as input? >> I think TableMapReduceUtil.initTableMapperJob() takes a single table as >> parameter. For my requirement, I want to specify multiple tables and scan >> instances. I read about MultiTableInputCollection in the document >> https://issues.apache.org/jira/browse/HBASE-3996. But I don't find it in >> HBase-0.92.0. >> >> >> >> Regards, >> >> Amlan >>
