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From Yue Liu <aimagol...@gmail.com>
Subject Re: Verifying that a query uses orc bloom filters, orc storage indexes
Date Fri, 31 Jul 2015 02:12:44 GMT
First, you need to know the total record number of your table.

After processing the query, then you can get the input record number of
MapReduce job from the counter "RECORDS_IN" of Hive or "Map input records"
of Map-Reduce Framework. If the input number is much smaller than the total
number, it shows the index is leveraged by query.

For improving the index performance, it is better to  sort your table by
the query dimensions.

2015-07-31 0:31 GMT+08:00 Jörn Franke <jornfranke@gmail.com>:

> Hi,
>
> Is there any official way to verify that a query leveraged orc bloom
> filters or orc indexes? For example, number of bytes (rows) not processed
> thanks to bloom filters or storage indexes? Some indicators in the explain
> output?
>
> Thank you.
>
> Best reagrds
>

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