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Date: Wed, 6 Oct 2010 12:15:15 -0500
Message-ID: <AANLkTi=-8xN1tn3zvOLpO6KxyuOm9k3xuWYsrqHxLw-O@mail.gmail.com>
Subject: Re: get keys based on values??
From: Tyler Hobbs <tyler@riptano.com>
To: user@cassandra.apache.org
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If you're interested in only checking part of a column's value, you can
generally
just store that part of the value in a different column.  So, have an
"email_addr" column
and a "email_domain" column, which stores "aol.com", for example.

Then you can just use a secondary index on the "email_domain" column.

- Tyler

On Wed, Oct 6, 2010 at 10:33 AM, Brayton Thompson <thompsbp@grnoc.iu.edu>wrote:

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> Ok, I am VERY new to Cassandra and trying to get my head around its core
> ideas.
>
> So lets say I have a CF of Users that contains all the info I would ever
> want to know about them. One day I decide(for some reason) that I want to
> send a mass email to only the users with AOL email addresses. Is there a
> mechanism for getting only keys whose email attribute contains the string @
> aol.com ? Or is this frowned upon? I could also envision separate CF's for
> each email type; that stored values to use as keys into my Users CF. Say the
> AOL CF contains the usernames of everyone that has an aol account. So I
> would pull all of the keys from that CF and then use them to index into the
> Users CF to pull their email addresses.  It seems to me that this is
> redundant. So I would like your thoughts on my example.
>
> Thank you,
> Brayton Thompson
> thompsbp@grnoc.iu.edu
> Global Research Network Operation Center
> Indiana University
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If you&#39;re interested in only checking part of a column&#39;s value, you=
 can generally<br>just store that part of the value in a different column.=
=A0 So, have an &quot;email_addr&quot; column<br>and a &quot;email_domain&q=
uot; column, which stores &quot;<a href=3D"http://aol.com">aol.com</a>&quot=
;, for example.<br>
<br>Then you can just use a secondary index on the &quot;email_domain&quot;=
 column.<br><br>- Tyler<br><br><div class=3D"gmail_quote">On Wed, Oct 6, 20=
10 at 10:33 AM, Brayton Thompson <span dir=3D"ltr">&lt;<a href=3D"mailto:th=
ompsbp@grnoc.iu.edu">thompsbp@grnoc.iu.edu</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin: 0pt 0pt 0pt 0.8ex; borde=
r-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">-----BEGIN PGP SI=
GNED MESSAGE-----<br>
Hash: SHA1<br>
<br>
Ok, I am VERY new to Cassandra and trying to get my head around its core id=
eas.<br>
<br>
So lets say I have a CF of Users that contains all the info I would ever wa=
nt to know about them. One day I decide(for some reason) that I want to sen=
d a mass email to only the users with AOL email addresses. Is there a mecha=
nism for getting only keys whose email attribute contains the string @<a hr=
ef=3D"http://aol.com" target=3D"_blank">aol.com</a> ? Or is this frowned up=
on? I could also envision separate CF&#39;s for each email type; that store=
d values to use as keys into my Users CF. Say the AOL CF contains the usern=
ames of everyone that has an aol account. So I would pull all of the keys f=
rom that CF and then use them to index into the Users CF to pull their emai=
l addresses. =A0It seems to me that this is redundant. So I would like your=
 thoughts on my example.<br>

<br>
Thank you,<br>
Brayton Thompson<br>
<a href=3D"mailto:thompsbp@grnoc.iu.edu">thompsbp@grnoc.iu.edu</a><br>
Global Research Network Operation Center<br>
Indiana University<br>
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</blockquote></div><br>

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