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From <xmanach....@orange-ftgroup.com>
Subject RE: Nodes Levels of Hierarchy in Cassandra.
Date Mon, 17 May 2010 10:05:15 GMT
Hi Benjamin.

  Ok.

Thank's for your anwser.


-----Message d'origine-----
De : Benjamin Black [mailto:b@b3k.us] 
Envoyé : lundi 17 mai 2010 00:08
À : user@cassandra.apache.org
Objet : Re: Nodes Levels of Hierarchy in Cassandra.

Not in Cassandra.

Your description of the levels is not quite accurate, either.  The keyspaces and CFs are generally
considered fixed since it is rather expensive to change them compared to the row keys and
columns.  Within an SCF, you have:

row_key: {supercolumn1: {column1A: value1A, column1B: value1B},
supercolumn2: {column2A: value2A, column2B: value2B}}

So the 3 levels of the hierarchy with SCFs are row
key->supercolumn->column.  You can certainly treat the SCF itself as a
4th level of the hierarchy if you like, but don't expect to add and remove them as you do
the 3 'dynamic' levels.


b

On Tue, May 11, 2010 at 8:51 AM,  <xmanach.ext@orange-ftgroup.com> wrote:
> Hi.
>
>   I undertstood I can use this structure with cassandra :
>
> KeySpace_3nodeslevels = {
>     Key_Family_alfa : {
>         Key_Super_Column_A : { Key_Column_1: "Value_alfa_A_1",
>                                Key_Column_2: "Value_alfa_A_2"},
>         Key_Super_Column_B : { Key_Column_1: "Value_alfa_B_1",
>                                Key_Column_2: "Value_alfa_B_2"}
},
>     Key_Family_beta : {
>         Key_Super_Column_A : { Key_Column_1: "Value_beta_A_1",
>                                Key_Column_2: "Value_beta_A_2"},
>         Key_Super_Column_B : { Key_Column_1: "Value_beta_B_1",
>                                Key_Column_2: "Value_beta_B_2"}
}
>              }
>
> I have 3 nodes levels of hierarchy for the keys : Key_Family, 
> Key_Super_Column and  Key_Column.
> I have around 100 Billions of keys for the Family level.
>
>   Can I have 4 nodes levels of hierarchy like this ?
>
> KeySpace_4nodeslevels = {
>     Key_level1_alfa : {
>         Key_level2_A : { Key_level3_1: { Key_level4_first  :
> "Value_alfa_A_1_first",
>                                          Key_level4_Second
:
> "Value_alfa_A_1_second"},
>                          Key_level3_2: { Key_level4_first  :
> "Value_alfa_A_2_first",
>                                          Key_level4_Second
:
> "Value_alfa_A_2_second"} },
>         Key_level2_B : { Key_level3_1: { Key_level4_first  :
> "Value_alfa_B_1_first",
>                                          Key_level4_Second
:
> "Value_alfa_B_1_second"},
>                          Key_level3_2: { Key_level4_first  :
> "Value_alfa_B_2_first",
>                                          Key_level4_Second
:
> "Value_alfa_B_2_second"} } },
>     Key_level1_beta : {
>         Key_level2_A : { Key_level3_1: { Key_level4_first  :
> "Value_beta_A_1_first",
>                                          Key_level4_Second
:
> "Value_beta_A_1_second"},
>                          Key_level3_2: { Key_level4_first  :
> "Value_beta_A_2_first",
>                                          Key_level4_Second
:
> "Value_beta_A_2_second"} },
>         Key_level2_B : { Key_level3_1: { Key_level4_first  :
> "Value_beta_B_1_first",
>                                          Key_level4_Second
:
> "Value_beta_B_1_second"},
>                          Key_level3_2: { Key_level4_first  :
> "Value_beta_B_2_first",
>                                          Key_level4_Second
:
> "Value_beta_B_2_second"} } }
>         }
>
> Thanks.
>
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This message and any attachments (the "message") are confidential and intended solely for
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Messages are susceptible to alteration. 
France Telecom Group shall not be liable for the message if altered, changed or falsified.
If you are not the intended addressee of this message, please cancel it immediately and inform
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