Re: MR output to a file instead of directory?
I'm not sure about the usecase, but if you really care you can use an existing directory (e.g. /) by writing a bit of code to bypass the check for output-dir existence... By default FIleOutputFormat assumes the output-dir shouldn't exist and will error out during init if it does. You could customize it to not bother to check. Arun On Mar 2, 2012, at 4:38 PM, Jianhui Zhang wrote: > Hi all, > > The FileOutputFormat/FileOutputCommitter always treats an output path > as a directory and write files under it, even if there is only one > Reducer. Is there any way to configure an OutputFormat to write all > data into a file? > > Thanks, > James -- Arun C. Murthy Hortonworks Inc. http://hortonworks.com/
Re: MR output to a file instead of directory?
James,
This is _possible_, but you will need a complete set of both
OutputFormat and OutputCommitter to do the work for you as
File{OutputFormat,OutputCommitter} work with directories. The biggest
advantage of having output directories is the ability to have
temporary attempt directories and output-committing (speculative
execution and task failure handling), described at
http://wiki.apache.org/hadoop/FAQ#Can_I_write_create.2BAC8-write-to_hdfs_files_directly_from_map.2BAC8-reduce_tasks.3F.
-- You'd need something like this for a complete solution.
On Sat, Mar 3, 2012 at 6:08 AM, Jianhui Zhang wrote:
> Hi all,
>
> The FileOutputFormat/FileOutputCommitter always treats an output path
> as a directory and write files under it, even if there is only one
> Reducer. Is there any way to configure an OutputFormat to write all
> data into a file?
>
> Thanks,
> James
--
Harsh J
MR output to a file instead of directory?
Hi all, The FileOutputFormat/FileOutputCommitter always treats an output path as a directory and write files under it, even if there is only one Reducer. Is there any way to configure an OutputFormat to write all data into a file? Thanks, James
