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Date: Wed, 28 Dec 2011 09:20:16 -0500
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Subject: Re: Merging 3 rows that are mostly read together from CF into single
 rows with composite col names ?
From: Edward Capriolo <edlinuxguru@gmail.com>
To: "user@cassandra.apache.org" <user@cassandra.apache.org>
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On Monday, December 26, 2011, Asil Klin <asdkl93@gmail.com> wrote:
> If 3 rows in a column family need to be read together 'always', is it
preferable to just merge them in 1 row using composite col names(instead of
keeping in 3 rows) ? Does this improve read performance, anyway ?

You almost definitely want to merge this row. In spinning disk systems like
SCSI or sata seeking data on disk is at a premium so having 3 independent
seeks for data that is always read together is not good.

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<br><br>On Monday, December 26, 2011, Asil Klin &lt;<a href=3D"mailto:asdkl=
93@gmail.com">asdkl93@gmail.com</a>&gt; wrote:<br>&gt; If 3 rows in a colum=
n family need to be read together &#39;always&#39;, is it preferable to jus=
t merge them in 1 row using composite col names(instead of keeping in 3 row=
s) ? Does this improve read performance, anyway ?<br>
<br>You almost definitely want to merge this row. In spinning disk systems =
like SCSI or sata seeking data on disk is at a premium so having 3 independ=
ent seeks for data that is always read together is not good.

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