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From Edward Capriolo <edlinuxg...@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 18:26:18 GMT
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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