Hi Jonathan Thanks for your reply. I had gone through the URL that you have specified. Let me put my problem statement with a clear statement:
We have a RDBMS table that contains Category ID, Section ID, Article, IS_Published column. Now the application that we currently have uses SQL and gets the data in various forms e.g. get all the articles that belong to a section, get all the articles that belong a specific category, specific section and which is published and so on. With your example, I understand that it is possible for me to have multiple columnfamilies and store the same data e.g: keyspace.category[WORLDNEWS][SECTION] = HOCKEY keyspace.category[WORLDNEWS][ARTICLE] = World cup hockey matches begin... keyspace.category[WORLDNEWS][IS_PUBLISHED] = TRUE and another set as keyspace.section[HOCKEY][CATEGORY] = WORLDNEWS keyspace.section[HOCKEY][ARTICLE] = World cup hockey matches begin... keyspace.section[HOCKEY][IS_PUBLISHED] = TRUE Now, if the above example is correct then I have following questions: 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. 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 :( Please help me out in understanding this basic difference between interpreting data in RDBMS world v/s NRDBMS world. On Fri, Jan 29, 2010 at 8:00 PM, Jonathan Ellis <jbel...@gmail.com> wrote: > Cassandra does not support ad-hoc queries the way SQL does. If you > want to ask "what rows have a column X containing value Y" then you > need to create a columnfamily whose keys are the values of X, and > whose columns are the keys of your original CF. > > Read http://arin.me/blog/wtf-is-a-supercolumn-cassandra-data-model if > you haven't yet. > > On Fri, Jan 29, 2010 at 6:16 AM, Mehar Chaitanya > <meharchaita...@gmail.com> wrote: > > Hi All > > > > I am a J2EE programmer only i had knowledge related to queries i will > query > > the sql where i can found the result. > > > > How can i use cassandra for my requirement is it possible? > > > > Below is my scenario > > > > - I have a table which contains columns like > > Category_name,Section_name,article,is_published_by with multiple > records > > in the table. > > - I want to retrieve a query based on condition like belongs some > > category_name 'X' . > > - Same will be applied to other 3 ,condition based on Section and > > is_published_by > > > > > > Please let me know if it would be possible. > > > > Thanks&Regards, > > Mehar Chaitanya Bandaru, > > Software Engineer, > > S cubes IT Solutions India Pvt. Ltd., > > http://www.scubian.com > > (W) +91 4040307821, > > (Cell) +91 9440 999 262, > > #4-1-319, 2nd Floor, Abids Road, Hyderabad - 01. > > >
