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From Mehar Chaitanya <>
Subject Re: Is this possible with cassandra
Date Sat, 30 Jan 2010 14:27:11 GMT
Hi Jonathan

I have gone through Lucandra , but i am a bit ambiguous for retrieving based
on multiple conditions.

In the previous example,

keyspace.category[WORLDNEWS][SECTION] = HOCKEY
keyspace.category[WORLDNEWS][ARTICLE] = World cup hockey matches begin...
keyspace.category[WORLDNEWS][IS_PUBLISHED] = TRUE

keyspace.category[WORLDNEWS][SECTION] = TENNIS
keyspace.category[WORLDNEWS][ARTICLE] = Australian Open...
keyspace.category[WORLDNEWS][IS_PUBLISHED] = TRUE

keyspace.category[WORLDNEWS][SECTION] = CRICKET
keyspace.category[WORLDNEWS][ARTICLE] = IPL 2010
keyspace.category[WORLDNEWS][IS_PUBLISHED] = FALSE

and another set as
keyspace.section[HOCKEY][CATEGORY] = WORLDNEWS
keyspace.section[HOCKEY][ARTICLE] = World cup hockey matches begin...
keyspace.section[HOCKEY][IS_PUBLISHED] = TRUE

keyspace.section[TENNIS][CATEGORY] = WORLDNEWS
keyspace.section[TENNIS][ARTICLE] = Australian Open...
keyspace.section[TENNIS][IS_PUBLISHED] = TRUE

keyspace.section[CRICKET][ARTICLE] = IPL 2010
keyspace.section[CRICKET][IS_PUBLISHED] = FALSE

I have two questions to ask

If i want to retrieve the result as alll values which have IS_PUBLISHED is

In the above case i have to get two column families join ? Am i correct or

I have to get the two queries which have IS_PUBLISHED =TRUE in one query
and  SECTION =CRICKET in another after getting the result again define
another set and retrive that.


After some days passed and database was changed like IPL2010 is also
published its value is true

I read that we have only INSERTS no UPDATE or DELETE in some blog

so then what to do with old one ?

Correct me if i am going in a wrong

Sorry for my english .

On Fri, Jan 29, 2010 at 11:36 PM, Jonathan Ellis <> wrote:

> On Fri, Jan 29, 2010 at 9:09 AM, Mehar Chaitanya
> <> wrote:
> >   1. This would lead to enourmous amount of duplication of data, in short
> >   if I now want to view the data from IS_PUBLISHED dimenstion then my
> database
> >   size would scale up tremendously.
> Yes.  But disk space is so cheap it's worth using a lot of it to make
> other things fast.
> >   2. Above way of reprensting the data would suffice if I want to
> retrieve
> >   something like, get me all the articles whose category is WORLDNEWS.
> But
> >   what if I want to find out something like: Get me all the articles
> whose
> >   Section is BASEBALL and Category is WORLDNEWS. For addressing queries
> taht
> >   depend on multiple parameter how do we do it? Hope I am clear with my
> >   problem statement :(
> You have to do the intersection client-side (or use something like
> to do it for you).
> -Jonathan

The difference between possible and impossible lies in person's

Mehar Chaitanya Bandaru,
Software Engineer,
S cubes IT Solutions India Pvt. Ltd.,
(W) +91 4040307821,
(Cell) +91 9440 999 262,
#4-1-319, 2nd Floor, Abids Road, Hyderabad - 01.

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