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From Wojciech Langiewicz <wlangiew...@gmail.com>
Subject Re: why 1 reducer on simple join?
Date Thu, 12 Jan 2012 23:00:29 GMT
Hello,
Have you tried running only select, without creating table? What are 
results?
How did you tried to set number of reducers? Have you used this:
set mapred.reduce.tasks = xyz;
How many mappers does this query use?

On 12.01.2012 23:53, Koert Kuipers wrote:
> I am running a basic join of 2 tables and it will only run with 1 reducer.
> why is that? i tried to set the number of reducers and it didn't work. hive
> just ignored it.
>
> create table z as select x.* from table1 x join table2 y where (
> x.col1 = y.col1 and
> x.col2 = y.col2 and
> x.col3 = y.col3 and
> x.col4 = y.col4 and
> x.col5 = y.col5
> );
>
> both tables are backed by multiple files / blocks / chunks
>

--
Wojciech Langiewicz

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