incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Uncle Mantis <uncleman...@gmail.com>
Subject Re: Cassandra basics
Date Sat, 24 Jul 2010 11:17:23 GMT
I want to point out my up hill battle tips. 

Make some friends in the Freenode #Cassandra IRC channel.

Stop hunting for formal documentation and just read all articles and examples you can get
a hold if regardless of it is Java or PHP or Ruby.

Take a look at Thrift and it's many wrappers.

There are some all star players in the community that you will continue to run into. Listen
to them. Do not be thick headed. Follow their advice. They know what they are talking about.
The last thing they want you to do is take the hard road if you do not have to.

Shouts to Benjamin Black and the rest of the #Cassandra crew that has helped me and put up
with me.

Sent from my iPhone

On Jul 24, 2010, at 12:50 AM, "themanatuf@juno.com" <themanatuf@juno.com> wrote:

> Sonia,
> 
> If you haven't visited the site below, I think it does the best job of explaining what
Cassandra is all about:
> 
> http://arin.me/blog/wtf-is-a-supercolumn-cassandra-data-model
> 
> Consider a group of ColumFamilies within a Keyspace like a group of tables in a database.
> 
> CompareWith tells Cassandra how to sort the data and it is sorted by the types you described.
So if you tell it to sort by UTF8Type it will consider the in the column that matches your
row key to be UTF8 data and will sort accordingly.
> 
> 
> 
> From: sonia gehlot <sonia.gehlot@gmail.com>
> To: user@cassandra.apache.org
> Subject: Cassandra basics
> Date: Fri, 23 Jul 2010 15:48:12 -0700
> 
> Hi Guys,
> 
> Recently I have started reading about Cassandra from the material available on net. But
I have very confused with the basic understanding of Cassandra. 
> I understand columnFamilies, supper columnFamilies but I have no clear understanding
of
> 
> 
> <Keyspace Name="Twitter">
>  <ColumnFamily CompareWith="UTF8Type" Name="Statuses" />
>  <ColumnFamily CompareWith="UTF8Type" Name="StatusAudits" />
> 
> 
>  <ColumnFamily CompareWith="UTF8Type" Name="StatusRelationships" CompareSubcolumnsWith="TimeUUIDType"
ColumnType="Super" />  
>  <ColumnFamily CompareWith="UTF8Type" Name="Users" />
> 
> 
>  <ColumnFamily CompareWith="UTF8Type" Name="UserRelationships" CompareSubcolumnsWith="TimeUUIDType"
ColumnType="Super" />
> </Keyspace>
> 
> 
> <ColumnFamily Name = "LocationUserIndexSCF"
>         CompareWith = "UTF8Types"
>         CompareSubcolumnsWith= "UTF8Type"
>         ColumnType = "Super"/> 
> 
> 1. I don't understand what is this "CompareWith", "CompareSuperColumnWith", "CompareSubcolumnsWith"
etc is?
> 
> 2. What is "UTF8Type", "TimeUUIDType", "LongType", "ASCIIType" etc.. is these are datatypes?
as we have datatype in SQL, if so then is this is datatype of value stored in this column
family?
> 
> 
> 
> May be I am getting confused because I am mixing my Relational databases fundamentals
with distributed.
> Please If someone can explain me significance of these things then it would be very helpful.
> 
> Thanks in advance.
> 
> Please reply.
> 
> Sonia 
> 
> 
> ____________________________________________________________
> FIRE SALE: iPads for $23.74?
> SPECIAL REPORT: iPads are being auctioned for an incredible 85% off!
> http://thirdpartyoffers.juno.com/TGL3131/4c4a393b224513eab65st05duc

Mime
View raw message