Cassandra入门

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http://www.iteye.com/topic/524977

这里简要介绍一下Cassandra入门，即安装和简单实用。

下载cassandra，http://cassandra.apache.org/download/
解压到 D:\apache-cassandra-0.5.1

创建环境变量 CASSANDRA_HOME = D:\apache-cassandra-0.5.1

设置conf/storage-conf.xml中的目录路径

<CommitLogDirectory>D:/cassandra/commitlog</CommitLogDirectory>
<DataFileDirectories>
<DataFileDirectory>D:/cassandra/data</DataFileDirectory>
</DataFileDirectories>
<CalloutLocation>D:/cassandra/callouts</CalloutLocation>
<StagingFileDirectory>D:/cassandra/staging</StagingFileDirectory>

运行 D:\apache-cassandra-0.5.1\bin>cassandra -f

启动后如下所示：

[img]http://dl.iteye.com/upload/attachment/233113/2fc097d2-9045-36b0-b8f6-f0e2c7cd5712.jpg[/img]

这里服务端便启动完毕，现在开启另一个cmd,在bin目录下运行cassandra-cli，即cassandra客户端。进入客户端后，键入connect localhost/9160 链接服务器。链接后如图：
[img]http://dl.iteye.com/upload/attachment/233116/4c38109a-b4bc-3a8e-a978-83a6979dc528.jpg[/img]

以下读写cassandra数据

cassandra> set Keyspace1.Standard1['jsmith']['first'] = 'John'
Value inserted.
cassandra> set Keyspace1.Standard1['jsmith']['last'] = 'Smith'
Value inserted.
cassandra> set Keyspace1.Standard1['jsmith']['age'] = '42'
Value inserted.
cassandra> get Keyspace1.Standard1['jsmith']
(column=age, value=42; timestamp=1249930062801)
(column=first, value=John; timestamp=1249930053103)
(column=last, value=Smith; timestamp=1249930058345)
Returned 3 rows.
cassandra>

  
set Keyspace1.Standard1['jsmith']['first'] = 'John'
       \            \         \        \          \
        \            \         \_ key   \          \_ value
         \            \                  \_ column
          \_ keyspace  \_ column family

Data stored in Cassandra is associated with a column family (Standard1),
which in turn is associated with a keyspace (Keyspace1). In the example
above, we set the value 'John' in the 'first' column for key 'jsmith'.