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From Jonathan Coveney <jcove...@gmail.com>
Subject Is there a reason why this simple query would take a very long time?
Date Mon, 24 Jan 2011 21:13:32 GMT
I have a 10 node server or so, and have been mainly using pig on it, but
would like to try out Hive.

I am running this query, which doesn't take too long in Pig, but is taking
quite a long time in Hive.

hive -e "select count(1) as ct from my_table where v1='02' and v2 =
11112222;" > thecount

One thing is that this job only uses 1 reducer, but it is taking most of its
time in its reduce step. I tried manually setting more reducers, but I think
that for a job without groups, it forces 1 reducer?

Either way, would love to know why this is dragging? It's worth noting that
my_table is not saved in the Hive format, but rather as a flat file. I
realize that this can influence performance, but shouldn't it at least
perform on par with pig?

Thanks for your help
Jon

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