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From "Kunal Khatua" <ku...@apache.org>
Subject Re: This query is so slow
Date Mon, 06 Aug 2018 17:41:01 GMT
Hi Peter

What does the profile for the query indicate?

Take a look at the operator overview. It will indicate which operator is using the most CPU
cycles. If the average and max processing times vary wildly, it might be a problem of skew,
where some fragments are doing a relatively excessive work.
If that is the case, within that operator's profile segment, you can see the distribution
of the fragments and see which ones are the long pole in your run.

~ KK 

On 8/6/2018 9:01:25 AM, Peter Edike <peter.edike@interswitchgroup.com> wrote:
Hello all,
The following query takes ages to complete in drill and more often that not, fails
select * from dfs.`/iswdata/rj/201805` where unique_key in
         select unique_key from dfs.`/iswdata/rj/201805` group by unique_key having
count(unique_key) > 1
limit 40
Please what can I do to improve the performance of this query
Kind Regards
Peter Edike
Senior Software Engineer
Research and Development, ENG

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