Questions tagged [mappers]
25 questions
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how to auto generate xml or yaml mappers from existing db in doctrine 2... but not using cli
I am new to ORM world and integrating doctrine 2 with zf project. I have gone through the doctrine documentation and various articles and integrated it :).
I have an existing DB from which I got to generate my mappers and entities. I am willing to…
Raj
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Hive - Randomly Distribute Records Across Mappers
I am looking for something like DISTRIBUTE BY but for mappers instead of reducers.
I have a map-only transform job that I am running, and using
SET mapred.min.split.size=2100000;
SET mapred.max.split.size=2100000;
To control the number of mappers…
Cry Wolf
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Number of DataNodes and MapTasks in Hadoop
how to set the number of DataNodes in Hadoop? is it by code, configuration, or environment decision.
Also during surfing the articles when someone says "The preferred number of maps around 10-100 maps per-node" so "node" here means NameNode or…
Mosab Shaheen
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Controlling mappers with hive table having around 800 part files
I have a hive table to which data gets added every day.
So, around 5 files get added each day.
Now we ended up having 800 part files under this table.
The issue i have is joining or using this table anywhere is triggering 800 mappers, as mappers are…
sushma
- 1
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generating Multiple output file from mapper in Hadoop MapReduce
I am working on producing two output files from mapper.I am using Multipleoutput api for producing two outputs.I am not sure ,if it is the correct way to do it .here is my code..
please go through this and give me your suggestions..when i run the…
Barath
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Hadoop Job stuck at map 0% reduce 0%
I am running a hadoop job which gets stuck at at "map 0% reduce 0%". More specifically, the mappers are all in the "STARTING" state and never seem to actually start executing.
I've tried looking at the logs but didn't really see anything other than…
Olshansky
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MapReduce Network Bandwidth
I am trying to measure the time consumed by each (key_a,value_a) pair transferred from a
mapper Mapper_i to a reducer Reducer_j.
In other words, I would like to know the time taken by (key_a,value_a) from leaving Mapper_i to reaching Reducer_j ?
Is…
user2262938
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class-table-mapper design php and ZF
is there a better way to work with ZF useing the mappers, real life objects and table_objects.
This is how I do it with Zend Framework:
class User_DbTable extends Zend_DB_Table_Abstract{
protected $_name = "user"; // name of the table
}
the…
Dr Casper Black
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Pseudo distributed : Need to change number of mapper nodes
I am using a Intel(R) Core(TM)2 Duo processor. I have installed hadoop in pseudo distributed mode. I have written a program which needs 50 mappers nodes. Is it possible to have 50 mapper nodes in the pseudo distributed mode or I will be limited to 4…
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Set Max number of mappers to 1 on Hive
I need to do sort of mapping from a string to an integer id, I was considering to do a UDF function and pass this string throw it. For this to work I need to have a single mapper.
How do I block the mappers to 1?
Thanks for the help
oleber
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