1. Lightning Introduction
to Cassandra
Michaël Figuière
@mfiguiere

2. Speaker
Michaël Figuière
@mfiguiere
©2012 DataStax 2

3. Ring Architecture
Node Node
Node Cassandra Node
Node
Node
©2012 DataStax 3

4. Ring Architecture
Node Replica
Node
Replica
Node
Replica
©2012 DataStax 4

5. Linear Scalability
Client Writes/s by Node Count - Replication Factor = 3
©2012 DataStax 5

6. Client / Server Communication
Client ? Node Replica
Client
Node
Replica
Client
Node
Client Replica
©2012 DataStax 6

7. Client / Server Communication
Client Node Replica
Client
Node
Replica
Client
Node
Client Replica
Coordinator node:
Forwards all R/W requests
to corresponding replicas
©2012 DataStax 7

8. Request Path
1
Client Node Replica
2
3
Client
4 2
Node
Replica
3
Client
2
3
Node
Client Replica
Coordinator node
©2012 DataStax 8

9. Column Family Data Model
name email address state
jbellis
Jonathan jb@ds.com 123 main TX
name email address state
dhutch
Daria dh@ds.com 45 2nd st CA
name email
egilmore
Eric eg@ds.com
Row Key Columns
©2012 DataStax 9

10. Column Family Data Model
dhutch egilmore datastax mzcassie
jbellis
egilmore
dhutch
datastax mzcassie
egilmore
Row Key Columns
©2012 DataStax 10

11. CQL3 Data Model
Timeline Table
user_id tweet_id author body
gmason 1765 phenry Give me liberty or give me death
gmason 1742 gwashington I chopped down the cherry tree
ahamilton 1797 jadams A government of laws, not men
ahamilton 1742 gwashington I chopped down the cherry tree
Partition Remaining
Key Key
©2012 DataStax 11

12. CQL3 Data Model
Timeline Table
user_id tweet_id author body
gmason 1765 phenry Give me liberty or give me death
gmason 1742 gwashington I chopped down the cherry tree
ahamilton 1797 jadams A government of laws, not men
ahamilton 1742 gwashington I chopped down the cherry tree
CQL
CREATE TABLE timeline (
user_id varchar,
tweet_id uuid,
author varchar,
body varchar,
PRIMARY KEY (user_id, tweet_id));
©2012 DataStax 12

13. CQL3 Data Model
Timeline Table
user_id tweet_id author body
gmason 1765 phenry Give me liberty or give me death
gmason 1742 gwashington I chopped down the cherry tree
ahamilton 1797 jadams A government of laws, not men
ahamilton 1742 gwashington I chopped down the cherry tree
Timeline Physical Layout
[1742, author] [1742, body] [1765, author] [1765, body]
gmason
gwashington I chopped down the... phenry Give me liberty or give...
[1742, author] [1742, body] [1797, author] [1797, body]
ahamilton
gwashington I chopped down the... jadams A government of laws...
©2012 DataStax 13

14. Stay Tuned!
blog.datastax.com
@mfiguiere