Appreciate your thoughts Tony,

in our DW there are composite keys, 500K of them say per customer to produce a report for which the client program needs to page through the entire set collecting data as it pages through yet to probably another desktop db.

At this point the purpose of having a NoSQL has been defeated.

On 06/26/2013 05:21 PM, Tony Anecito wrote:
Thanks Arthur.

Interesting you think NoSQL does not fit into large volumes of data, That is what it is touted to do.
I have heard PK's are needed but remember that is what the "key" column is for I thought and composite key support is there also.

The only issue I see is the all that duplicate data and a need to keep it in sync. So for example if the movie title "Superman" changed to "Superman the Man of Steel" you have to go change all those duplicate values. An easy problem to solve but the data modeler has to get past that. lol

Acid transactions is the other but I think then the supplier of info has to think about that one.

I have response times in my RDMS of several hundred microseconds which is the really important requirement for me to keep that the same or better.

Just some thoughts on the matter.
-Tony


From: Arthur Zubarev <Arthur.Zubarev@Aol.com>
To: Tony Anecito <adanecito@yahoo.com>; Robert Coli <rcoli@eventbrite.com>; Users-Cassandra <user@cassandra.apache.org>
Sent: Wednesday, June 26, 2013 3:08 PM
Subject: Re: Creating an "Index" column...

Tony hi,
 
Yes, in some scenarios (e.g. a DW), e.g. absence of proper PKs or indexes (just too hard to envision, you need to think of future queries 1st) getting thru large volumes of data makes NoSQL IMHO hard to fit in.
 
But you have other choices:
 
1) pagination or
2) slice queries.
 
Both of that is covered here:
 
 
Hope that helps.
 
/Arthur
 
Sent: Wednesday, June 26, 2013 1:55 PM
Subject: Re: Creating an "Index" column...
 
Hi Robert,

Actually that is what I did. I did that in my RDMS data model. In Cassandra or NOSQL without join or nested selects I have to do two queries. Also, since batching is not supported on the server side which makes the performance worse.

I just started learning Cassandra but I am learning fast and there are some challenges when moving to a new data model driven by these factors.

Regards,
-Tony

 

From: Robert Coli <rcoli@eventbrite.com>
To: user@cassandra.apache.org; Tony Anecito <adanecito@yahoo.com>
Sent: Wednesday, June 26, 2013 11:32 AM
Subject: Re: Creating an "Index" column...

On Wed, Jun 26, 2013 at 10:20 AM, Tony Anecito <adanecito@yahoo.com> wrote:
> Never mind I figured it out. I found it via a search for Secondary indexes.

In general unless you actually need atomic update of the row and its
secondary index, you are probably better off creating your own pseudo
secondary index column family.

=Rob






-- 

Regards,

Arthur