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From Marcelo Elias Del Valle <mvall...@gmail.com>
Subject Correct model
Date Wed, 19 Sep 2012 19:02:16 GMT
I am new to Cassandra and NoSQL at all.
I built my first model and any comments would be of great help. I am
describing my thoughts bellow.

It's a very simple model. I will need to store several users and, for each
user, I will need to store several requests. It request has it's insertion
time. As the query comes first, here are the only queries I will need to
run against this model:
- Select all the requests for an user
- Select all the users which has new requests, since date D

I created the following model: an UserCF, whose key is a userID generated
by TimeUUID, and a RequestCF, whose key is composite: UserUUID + timestamp.
For each user, I will store basic data and, for each request, I will insert
a lot of columns.

My questions:
- Is the strategy of using a composite key good for this case? I thought in
other solutions, but this one seemed to be the best. Another solution would
be have a non-composite key of type UUID for the requests, and have another
CF to relate user and request.
- To perform the second query, instead of selecting if each user has a
request inserted after date D, I thought in storing the last request
insertion date into the userCF, everytime I have a new insert for the user.
It would be a data replication, but I would have no read-before-write and I
am guessing the second query would perform faster.

Any thoughts?

-- 
Marcelo Elias Del Valle
http://mvalle.com - @mvallebr

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