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Date: Mon, 23 Jul 2012 19:37:38 +0300
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 <CAEL31iLtZG2s8mLOV0Go_hf+fMufvUZWp_Nb1o=wRxN+6Y-LLA@mail.gmail.com>
Subject: Re: Schema advice: (Single row or multiple row!?) How do I store
 millions of columns when I need to read a set of around 500 columns at a
 single read query using column names ?
From: Eldad Yamin <eldad87@gmail.com>
To: user@cassandra.apache.org
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in addition, if you don't know how many rows will be needed - in each row,
you can store the key of the next one.
Just like in a linked list.

OR

have 1 row that will hold all the keys that combining your other rows.
1st select the main row (with the keys), then select the other rows.


On Mon, Jul 23, 2012 at 3:40 PM, rohit bhatia <rohit2412@gmail.com> wrote:

> You should probably try to break the one row scheme to
> 2*Number_of_nodes rows scheme.. This should ensure proper distribution
> of rows and still allow u to query from a few fixed number of rows.
> How u do it depends on how are u gonna choose ur 200-500 columns
> during reading (try having them in the same row)
>
> Even if u r forced to put them in seperate rows, u can make the row
> key as "some modulus of hash of column name", ensuring symmetry and
> easy access of columns...
>
> On Mon, Jul 23, 2012 at 6:02 PM, Ertio Lew <ertiop93@gmail.com> wrote:
> > Any ideas/suggestions please?
>

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<div dir=3D"ltr">in addition, if you don&#39;t know how many rows will be n=
eeded -=A0in each row, you can store the key of the next one.<div><div>Just=
 like in a linked list.</div><div><br></div><div>OR</div><div><br></div><di=
v>
have 1 row that will hold all the keys that combining your other rows.</div=
><div>1st select the main row (with the keys), then select the other rows.<=
/div><div><br><div><div><br><br><div class=3D"gmail_quote">On Mon, Jul 23, =
2012 at 3:40 PM, rohit bhatia <span dir=3D"ltr">&lt;<a href=3D"mailto:rohit=
2412@gmail.com" target=3D"_blank">rohit2412@gmail.com</a>&gt;</span> wrote:=
<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">You should probably try to break the one row=
 scheme to<br>
2*Number_of_nodes rows scheme.. This should ensure proper distribution<br>
of rows and still allow u to query from a few fixed number of rows.<br>
How u do it depends on how are u gonna choose ur 200-500 columns<br>
during reading (try having them in the same row)<br>
<br>
Even if u r forced to put them in seperate rows, u can make the row<br>
key as &quot;some modulus of hash of column name&quot;, ensuring symmetry a=
nd<br>
easy access of columns...<br>
<br>
On Mon, Jul 23, 2012 at 6:02 PM, Ertio Lew &lt;<a href=3D"mailto:ertiop93@g=
mail.com">ertiop93@gmail.com</a>&gt; wrote:<br>
&gt; Any ideas/suggestions please?<br>
</blockquote></div><br></div></div></div></div></div>

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