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Date: Sat, 11 Jul 2015 11:42:47 +0800
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 <CAGeA17RaVj24OeZh+-6mq0QUEiU3rUd8DyVXuknQKdg4dqGcYQ@mail.gmail.com>
Subject: How to use the index in Parquet to improve the query
From: Yue Liu <aimagolymk@gmail.com>
To: user@hive.apache.org
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Hi, All,

I am using Hive-1.2.1, and store table as Parquet. Now I have a query as
below:

select count(1)
from lineitem
where l_quantity=1.0;

I read the document of Parquet, it said Parquet have the similar Min and
Max statistics like ORC to filter unrelated data.

But I notice that the records number showed by Counter RECORDS_IN is the
same with the whole table.

That is, the index in Parquet does not work.

What are the reasons?

Thanks!

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<div dir=3D"ltr">Hi, All,<div><br></div><div>I am using Hive-1.2.1, and sto=
re table as Parquet. Now I have a query as below:</div><div><br></div><div>=
select count(1)</div><div>from lineitem</div><div>where l_quantity=3D1.0;</=
div><div><br></div><div>I read the document of Parquet, it said Parquet hav=
e the similar Min and Max statistics like ORC to filter unrelated data.</di=
v><div><br></div><div>But I notice that the records number showed by Counte=
r=C2=A0<span style=3D"color:rgb(0,0,0);font-family:sans-serif;font-size:med=
ium">RECORDS_IN=C2=A0</span>is the same with the whole table.</div><div><br=
></div><div>That is, the index in Parquet does not work.</div><div><br></di=
v><div>What are the reasons?</div><div><br></div><div>Thanks!</div></div>

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