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From Martin Arrowsmith <arrowsmith.mar...@gmail.com>
Subject Re: Retrieve all composite columns from a row, whose composite name's first component matches from a list of Integers
Date Wed, 28 Dec 2011 19:04:23 GMT
I believe this calls for Cassanda Cookbook 2nd edition :)

On Wed, Dec 28, 2011 at 10:26 AM, Edward Capriolo <edlinuxguru@gmail.com>wrote:

> Super columns have the same fundamental problem and perform worse in
> general. So switching from composites to super columns is NEVER a good idea.
>
>
> On Wed, Dec 28, 2011 at 1:19 PM, Aditya <adynnn@gmail.com> wrote:
>
>> Since I have around 20 items to query, I guess making 20 queries to
>> retrieve activities by all followies on all of those 20 columns would too
>> inefficient, so to take the advantage of more efficient queries, are
>> supercolumns recommended for this case ? Anyways, in case I use
>> supercolumns, I need to retrieve the entire supercolumn at any point of
>> time & I am writing subcolumn(s) to the supercolumn at different times not
>> at once.
>>
>> On Wed, Dec 28, 2011 at 8:07 PM, Edward Capriolo <edlinuxguru@gmail.com>wrote:
>>
>>> You need to execute one get slice operation for each item id or if the
>>> row is not large , you can try one large get slice on the entire row and
>>> deal with the results client side.
>>>
>>> If you try method 1 When doing slices on composites you can set the
>>> start inclusive or exclusive values to get only the column you want and not
>>> some extra columns up to slice range size.
>>>
>>>
>>> On Tuesday, December 27, 2011, Aditya <adynnn@gmail.com> wrote:
>>> > I need to store data of all activities by user's followies in single
>>> row. I am trying to do that making use of composite column names in a
>>> single user specific row named 'rowX'.
>>> > On any activity by a user's followie on an item, a column is stored in
>>> 'rowX'. The column has a composite type column name made up of
>>> itemId+userId (which makes it unique col. name) in rowX. (& column value
>>> contains the activity data related to that item by that followie)
>>> >
>>> > Now I want to retrieve activity by all users on a list of items. So I
>>> need to retrieve all composite columns with composite's first component
>>> matching the itemId. Is it possible to do such a query to Cassandra ? I am
>>> using Hector.
>>>
>>
>>
>

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