The database industry has been abuzz over the past year about NoSQL databases. Apache Cassandra, which has quickly emerged as a best-of-breed solution in this space, is used at many companies to achieve unprecedented scale while maintaining streamlined operations. This presentation goes beyond the hype, buzzwords, and rehashed slides and actually presents the attendees with a hands-on, step-by-step tutorial on how to write a Java application on top of Apache Cassandra. It focuses on concepts such as idempotence, tunable consistency, and shared-nothing clusters to help attendees get started with Apache Cassandra quickly while avoiding common pitfalls.

3. CAP Theorem C onsistency A vailability P artition Tolerance “ Though shalt have but 2” - Conjecture made by Eric Brewer in 2000 - Published as formal proof in 2002 - See: http://en.wikipedia.org/wiki/CAP_theorem for more

5. Generally complements another system(s) (Not intended to be one-size-fits-all) *** You should always use the right tool for the right job anyway

6. How does this differ from an RDBMS?

7. How does this differ from an RDBMS? Substantially.

8. vs. RDBMS - No Joins Unless: - you do them on the client - you do them via Map/Reduce

9. vs. RDBMS - Schema Optional (Though you can add meta information for validation and type checking) *** Supports secondary indexes too: “ … WHERE state = 'TX' ”

10. vs. RDBMS - Prematerialized and Transaction-less - No ACID transactions - Limited support for ad-hoc queries

11. vs. RDBMS - Prematerialized and Transaction-less - No ACID transactions - Limited support for ad-hoc queries *** You are going to give up both of these anyway when you shard an RDBMS ***

13. vs. RDBMS - Shared-Nothing Architecture Every node plays the same role: no masters, no slaves, no special nodes *** No single point of failure

39. - Controls replication

40. Column Family

41. - Similar to a table

42. - Columns ordered by name

44. Dynamic Column Family

45. - Pre-calculated query results

46. Nothing stopping you from mixing them!

49. Data Model – Prematerialized Query Additional examples: Timeline of tweets by a user Timeline of tweets by all of the people a user is following List of comments sorted by score List of friends grouped by state

52. Using a Client Hector Client: http://hector-client.org - Most popular Java client - In use at very large installations - A number of tools and utilities built on top - Very active community - MIT Licensed *** like any open source project fully dependent on another open source project it has it's worts

62. - Merge on read

63. - Sstables are immutable

64. - Highest timestamp wins

66. -------------------

67. RowKey: CA Burlingame

68. => (column=650, value=33372e3537783132322e3334, timestamp=1310340410528000)

69. -------------------

70. RowKey: TX Austin

71. => (column=202, value=33302e3237783039372e3734, timestamp=1310143852392000)

72. => (column=203, value=33302e3237783039372e3734, timestamp=1310143852444000)

73. => (column=204, value=33302e3332783039372e3733, timestamp=1310143852448000)

74. => (column=205, value=33302e3332783039372e3733, timestamp=1310143852453000)

75. => (column=206, value=33302e3332783039372e3733, timestamp=1310143852457000)

77. -------------------

78. RowKey: CA Burlingame

79. -------------------

80. RowKey: TX Austin

81. => (column=202, value=33302e3237783039372e3734, timestamp=1310143852392000)

82. => (column=203, value=33302e3237783039372e3734, timestamp=1310143852444000)

83. => (column=204, value=33302e3332783039372e3733, timestamp=1310143852448000)

84. => (column=205, value=33302e3332783039372e3733, timestamp=1310143852453000)

85. => (column=206, value=33302e3332783039372e3733, timestamp=1310143852457000)

87. . . .

88. -------------------

89. RowKey: 202230

90. -------------------

91. . . .

95. class="me.prettyprint.cassandra.service.CassandraHostConfigurator">

96. <constructor-arg value=&quot;localhost:9170&quot;/>

97. </bean>

98. <bean id=&quot;cluster&quot; class=&quot;me.prettyprint.cassandra.service.ThriftCluster&quot;>

99. <constructor-arg value=&quot;TestCluster&quot;/>

100. <constructor-arg ref=&quot;cassandraHostConfigurator&quot;/>

101. </bean>

102. <bean id=&quot;consistencyLevelPolicy&quot; class=&quot;me.prettyprint.cassandra.model.ConfigurableConsistencyLevel&quot;>

103. <property name=&quot;defaultReadConsistencyLevel&quot; value=&quot;ONE&quot;/>

104. </bean>

105. <bean id=&quot;keyspaceOperator&quot; class=&quot;me.prettyprint.hector.api.factory.HFactory&quot;

106. factory-method=&quot;createKeyspace&quot;>

107. <constructor-arg value=&quot;Keyspace1&quot;/>

108. <constructor-arg ref=&quot;cluster&quot;/>

109. <constructor-arg ref=&quot;consistencyLevelPolicy&quot;/>

110. </bean>

111. <bean id=&quot;simpleCassandraDao&quot; class=&quot;me.prettyprint.cassandra.dao.SimpleCassandraDao&quot;>

112. <property name=&quot;keyspace&quot; ref=&quot;keyspaceOperator&quot;/>

113. <property name=&quot;columnFamilyName&quot; value=&quot;Standard1&quot;/>

114. </bean>

116. https://github.com/rantav/hector/wiki/Hector-Object-Mapper-%28HOM%29

117. Hector JPA:

118. https://github.com/riptano/hector-jpa

120. JdbcTemplate FTW!

122. CCM localhost cassandra cluster https://github.com/pcmanus/ccm

126. - Bank account:

127. “ on values over $10,000, wait to here from all replicas”

128. - Distributed Shopping Cart:

129. Show a confirmation page to verify order resolution

130. *** What is your appetite for risk?

133. ***But In an append-only system, we don't do updates

135. - Look for idempotence and asynchronicity in your business processes

136. - If it's not in the API, you are probably doing it wrong

137. - Seek death is still possible if you model incorrectly

140. Apache Cassandra project wiki: http://wiki.apache.org/cassandra/

141. “ The Dynamo Paper”

142. http://www.allthingsdistributed.com/files/amazon-dynamo-sosp2007.pdf

143. P. Helland. Building on Quicksand

144. http://arxiv.org/pdf/0909.1788

145. P. Helland. Life Beyond Distributed Transactions

146. http://www.ics.uci.edu/~cs223/papers/cidr07p15.pdf

147. S. Anand. “Netflix's Transition to High-Availability Storage Systems”

148. http://media.amazonwebservices.com/Netflix_Transition_to_a_Key_v3.pdf

149. “ The Megastore Paper”

150. http://research.google.com/pubs/archive/36971.pdf