Would you like to learn how to use Cassandra but don’t know where to begin? Want to get your feet wet but you’re lost in the desert? Longing for a cluster when you don’t even know how to set up a node? Then look no further! Rebecca Mills, Junior Evangelist at Datastax, will guide you in the webinar “Getting Started with Apache Cassandra...” You'll get an overview of Planet Cassandra’s resources to get you started quickly and easily. Rebecca will take you down the path that's right for you, whether you are a developer or administrator. Join if you are interested in getting Cassandra up and working in the way that suits you best.

1. ©2013 DataStax Confidential. Do not
Rebecca Mills
Junior Evangelist
DataStax
@rebccamills
Getting Started with Apache Cassandra
1

2. • Then you’ve come to the
right place!
• To learn some important
basics of Cassandra
without ever having to
leave your couch
Don’t want to spend exorbitant amount of
time and energy learning a new database?

3. What do I do?
• Try to create awareness
for open source Cassandra
• Develop content to get
people interested in trying
• Identify problems
newcomers might be
encountering
• Develop strategies and
material to help with that

4. Where can you download Cassandra?
• The easiest way is to
head straight to Planet
Cassandra
• http://planetcassandra.or
• Go to the “Downloads”
section, choose you
operating system and the
version of DSC that’ you’d
like
• Get crackin’!

5. Let’s get started

6. 2 things you should do to get going
1.Check your version of
Java
2.Edit your cassandra.yaml
file to point your
Cassandra instance
towards your home
directory

7. 1. Check your version of Java
• To check what version of java
you are using, at the prompt
type
% java –version
•Be sure to use the latest
version (JDK 7) on all nodes

8. 2. Change default location to save data
• Don’t run Cassandra as
root
• Other wise we will not be
able to start Cassandra
or have access to the
directories where our data
is being saved.
• Access the cassandra.yaml
file though the cassandra
conf directory

9. The 3 lines you should change in the
cassandra.yaml file:
Edit cassandra.yaml
data_file_directories:
- /var/lib/cassandra/data
-$HOME/cassandra/data
commitlog_directory: /var/lib/cassandra/commitlog
$HOME/cassandra/commitlog
saved_caches_directory: /var/lib/cassandra/saved_caches
$HOME/cassandra/saved_caches

10. 1.Start up an instance
1.Create a schema with CQL
2.Inject some data into our
instance
1.Run a query against our
database
5 things you can do quickly

11. 1. Start up an instance
• It’s very simple! Just go to
your install location and start
it from the bin directory as
such:
$ cd install_location
$ bin/cassandra

12. 2. Create a schema with CQL
• From within your installation
directory, start up your CQL
shell from within the bin
directory
$ cd install_directory
$ bin/cqlsh
• You should see the cqlsh
command prompt as such
Connected to Test Cluster at localhost:9160.
[cqlsh 4.1.1 | Cassandra 2.0.8 | CQL spec 3.1.1 | Thrift protocol 19.39.0]
Use HELP for help.
cqlsh>

13. 2. Create a schema with CQL
• A keyspace is a container for
our data. Here we are creating
a demo keyspace and a users
table within. A table consists
of rows and columns.
CREATE KEYSPACE demo WITH REPLICATION =
{‘class’:’SimpleStrategy’,’replication_factor’:1};
USE demo;
CREATE TABLE users (
firstname text,
lastname text,
age int,
email text,
city text,
PRIMARY KEY (lastname)
);

14. 3. Inject some data into your instance
• Nothing sadder than an empty database. Here we
are populating our “users” table with rows of
data using the INSERT command.
INSERT INTO users (firstname, lastname, age, email, city) VALUES
(‘John’,’Smith’, 46, ‘johnsmith@email.com’, ‘Sacramento’);
INSERT INTO users (firstname, lastname, age, email, city) VALUES
(‘Jane’,’Doe’, 36, ‘janedoe@email.com’, ‘Beverly Hills’);
INSERT INTO users (firstname, lastname, age, email, city) VALUES
(‘Rob’,’Byrne’, 24, ‘robbyrne@email.com’, ‘San Diego’);

15. 4. Make a query against your database
SELECT * FROM users;
SELECT * FROM users WHERE lastname=‘Doe’;
lastname | age | city | email | firstname
----------+-----+---------------+---------------------+-----------
Doe | 36 | Beverly Hills | janedoe@email.com | Jane
Bryne | 24 | San Diego | robbyrne@email.com | Rob
Smith | 46 | Sacramento | johnsmith@email.com | John
lastname | age | city | email | firstname
----------+-----+---------------+-------------------+-----------
Doe | 36 | Beverly Hills | janedoe@email.com | Jane

16. 5. Make a change to your data
UPDATE users SET city=‘San Jose’ WHERE lastname=‘Doe’;
SELECT * FROM users WHERE lastname= ‘Doe’;
lastname | age | city | email | firstname
----------+-----+----------+-------------------+-------------
Doe | 36 | San Jose | janedoe@email.com | Jane
SELECT * FROM users;DELETE FROM users WHERE lastname=‘Doe’;
lastname | age | city | email | firstname
----------+-----+---------------+---------------------+-----------
Bryne | 24 | San Diego | robbyrne@email.com | Rob
Smith | 46 | Sacramento | johnsmith@email.com | John

17. Two really neat tools:
1. Opscenter
2. DevCenter

18. Dev Center
• Try out your CQL in an easy-
to-use tool
• Has most of the same
functionality as cqlsh with
a few exceptions
• Quickly connect to your
cluster and keyspace. GO!

25. Opscenter
• Opscenter makes it easy to
manage and configure your
cluster!

26. Change configurations
• Just a couple clicks and you
can reconfigure an entire
cluster.

27. Metrics
• Diagnosis problems with your
cluster

28. How about multi datacenter?
Of course!

29. You can run an AWS AMI from Opscenter!
• Run a Cassandra instance/cluster in the
cloud!
• Using Amazon Web Services EC2 Management
Console
• Quickly deploy a Cassandra cluster within
a single availability zone through
Opscenter
• Check out
http://www.datastax.com/documentation/cassa

32. What about the drivers
• Datastax provides drivers
for Java, Python, C#, and C+
+
• There are also many open
sources community drivers,
including Closure, Go,
Node.js and many many
more.

33. Connect to your instance with Java
• Create a new Java class,
com.example.cassandra.SimpleClient for
example
• Add an instance field to hold cluster
reference
private Cluster cluster;
• Add an instance method, connect, to your
new class. Here you can add your contact
point, the ip address of your node.
public void connect(String node) {
cluster = Cluster.builder()
.addContactPoint(<ip_address>)
.build();
}
• Add an instance method, close, to shut
down the cluster once you are finished

34. Connect to your instance with Java
• In your main class, create a SimpleClient
object, call connect, and close it
public static void main(String[] args) {
SimpleClient client = new SimpleClient();
client .connect(<ip_address>);
client.close();
}
• Select some data
session.execute (‘SELECT * FROM demo.users’);

35. Connect to your instance in Python
• From cassandra.cluster import Cluster
cluster = Cluster()
• This will attempt to connect to a cluster
on your local machine.
You could also give it an ip address and it
will connect to that.
cluster = Cluster(<ip_address>)
• To connect to a node and begin begin
actually running queries against our
instance, we need a session, which is
created by calling Cluster.connect()
cluster = Cluster()
Session = cluster.connect()
• You can even connect to a particular
keyspace
cluster = Cluster()
Session = cluster.connect(‘demo’)

36. Connect to your instance in Python
• Select some data
results = session.execute (”””
SELECT * FROM demo.users
“““)

37. Get familiar
• Visit
http://planetcassandra.org
• Your #1 destination for
NoSQL Apache Cassandra
resources
• Downloads, webinars,
presentations, blog posts,
and much, much more!

38. Try Cassandra

39. Thank you!!
Any Questions?