Mailing-List: contact user-help@hive.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@hive.apache.org
Received-SPF: pass (nike.apache.org: domain of ricky@cloudera.com designates
 209.85.219.51 as permitted sender)
MIME-Version: 1.0
In-Reply-To: 
 <CACkSZy0wKP1M=F7KLDqch2gt8DvJ+EtQ6HVx6khMM0Q23nV0dw@mail.gmail.com>
References: 
 <CACkSZy3BTPdr9MVs+MJkPOCrQHvD=vxcMyFeUMnYdh2r0m--rg@mail.gmail.com>
	<CAEcou0RpR4-Nhi1bNZJO9FPJNECYCTNSikteiAetV2iP5WoaYA@mail.gmail.com>
	<CACkSZy0wKP1M=F7KLDqch2gt8DvJ+EtQ6HVx6khMM0Q23nV0dw@mail.gmail.com>
Date: Tue, 20 Aug 2013 22:18:53 -0400
Message-ID: 
 <CAEcou0TAaJ9Ooqk950B0FSpk5yqrrTQ60e2V3Q=SLb57G3dwhg@mail.gmail.com>
Subject: Re: Any Scenarios in which Views impose performance penalties
From: Ricky Saltzer <ricky@cloudera.com>
To: user@hive.apache.org
Content-Type: multipart/alternative; boundary=089e01227e6c850f2504e46bcb22

--089e01227e6c850f2504e46bcb22
Content-Type: text/plain; charset=ISO-8859-1

Since this bug was in Impala's query planner, I'm sure Hive is unaffected.
On Aug 20, 2013 10:15 PM, "Stephen Boesch" <javadba@gmail.com> wrote:

>
> Thanks v much Ricky.  Is this fixed in hive 0.11 - or going to be later
> i.e. 0.12?
>
>
> 2013/8/20 Ricky Saltzer <ricky@cloudera.com>
>
>> Although this is already fixed in the next and upcoming impala release,
>> you might want to be aware of the following view limitation.
>>
>> https://issues.cloudera.org/browse/IMPALA-495
>> On Aug 20, 2013 7:16 PM, "Stephen Boesch" <javadba@gmail.com> wrote:
>>
>>> Views should theoretically not incur performance penalties: they simply
>>> represent queries. Are there situtions that things are "not that simple" -
>>> i.e. views may actually result in different exeucution plans than the
>>> underlying sql?
>>>
>>> Additionally, are there views-related bugs that we should be aware of
>>> that would limit the occasions that we could use them?
>>>
>>> Thanks for the pointers.
>>>
>>>
>>>
>

--089e01227e6c850f2504e46bcb22
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

<p dir=3D"ltr">Since this bug was in Impala&#39;s query planner, I&#39;m su=
re Hive is unaffected. </p>
<div class=3D"gmail_quote">On Aug 20, 2013 10:15 PM, &quot;Stephen Boesch&q=
uot; &lt;<a href=3D"mailto:javadba@gmail.com">javadba@gmail.com</a>&gt; wro=
te:<br type=3D"attribution"><blockquote class=3D"gmail_quote" style=3D"marg=
in:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir=3D"ltr"><br><div>Thanks v much Ricky. =A0Is this fixed in hive 0.1=
1 - or going to be later i.e. 0.12?</div></div><div class=3D"gmail_extra"><=
br><br><div class=3D"gmail_quote">2013/8/20 Ricky Saltzer <span dir=3D"ltr"=
>&lt;<a href=3D"mailto:ricky@cloudera.com" target=3D"_blank">ricky@cloudera=
.com</a>&gt;</span><br>

<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex"><p dir=3D"ltr">Although this is already fixe=
d in the next and upcoming impala release, you might want to be aware of th=
e following view limitation. </p>


<p dir=3D"ltr"><a href=3D"https://issues.cloudera.org/browse/IMPALA-495" ta=
rget=3D"_blank">https://issues.cloudera.org/browse/IMPALA-495</a></p><div><=
div>
<div class=3D"gmail_quote">On Aug 20, 2013 7:16 PM, &quot;Stephen Boesch&qu=
ot; &lt;<a href=3D"mailto:javadba@gmail.com" target=3D"_blank">javadba@gmai=
l.com</a>&gt; wrote:<br type=3D"attribution"><blockquote class=3D"gmail_quo=
te" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"=
>


<div dir=3D"ltr">Views should theoretically not incur performance penalties=
: they simply represent queries. Are there situtions that things are &quot;=
not that simple&quot; - i.e. views may actually result in different exeucut=
ion plans than the underlying sql? =A0<div>


<br></div><div>Additionally, are there views-related bugs that we should be=
 aware of that would limit the occasions that we could use them?</div><div>=
<br></div><div>Thanks for the pointers.</div><div><br></div><div><br></div>


</div>
</blockquote></div>
</div></div></blockquote></div><br></div>
</blockquote></div>

--089e01227e6c850f2504e46bcb22--