Hi,
Please read the map section of
http://wiki.apache.org/hadoop/HadoopMapReduce to understand how Hadoop
ends up respecting record boundaries despite block-chops not taking
that into consideration. I hope it helps clear things up for you.
On Fri, Feb 10, 2012 at 10:26 PM, GUOJUN Zhu
Hi, all,
I am starting to learn advanced Map/Reduce. However, I cannot find the
class DataJoinMapperBase in my downloaded Hadoop 1.0.0 and 0.20.2. So I
searched on the Web and get the following link.
http://www.java2s.com/Code/Jar/h/Downloadhadoop0201datajoinjar.htm
From the link I got the
Thank you for the reply. That page helps a lot. I still have a more
specific question. In a LineRecordReader's constructor (hadoop 1.0.0)
public LineRecordReader(Configuration job, FileSplit split). Does a call
final Path file = split.getPath() return the logical file in HDFS or
just the
Bing,
You should find the data_join contrib module under
./src/contrib/data_join, and you should be able to build from that if
its jar does not also pre-exist under ./contrib/data_join.
On Sat, Feb 11, 2012 at 1:09 AM, Bing Li lbl...@gmail.com wrote:
Hi, all,
I am starting to learn advanced
Hi harsh, i am trying to find what are all the rowkeys present in two
tables. If userid is the rowKey for two different tables, i want to find
all those rowsKeys present in both thae tables. Fo that i need to read from
two tables into a mapreduce job. i.e i want to take multiple tables as
input to
Hi Zhu,
Ø The LineRecordReader will get the path in the HDFS itself, not on the
LocalFileSystem,
But its the NameNode who gives the list of DataNodes for a particular
block, sorted by the Distance from the Client. i.e. Here Machine where Task
is Running.
Ø For the line which ends
