我想使用 Hive 来查询 HBase 表的数据，例如：
100 column=cf1:val, timestamp=1379536809907, value=val_100
我在 hive 中键入以下命令：
select * from hbase_table where value = 'val_100';
我相信一切都已经安排好了。当我输入上面的命令时，它显示我是这样的：
Total MapReduce jobs = 1
Launching Job 1 out of 1
Number of reduce tasks is set to 0 since there's no reduce operator
Starting Job = job_201309031344_0024, Tracking URL = http://namenode:50030/jobdetails.jsp?jobid=job_201309031344_0024
Kill Command = /usr/libexec/../bin/hadoop job -kill job_201309031344_0024
Hadoop job information for Stage-1: number of mappers: 1; number of reducers: 0
2013-09-18 14:45:53,815 Stage-1 map = 0%, reduce = 0%
2013-09-18 14:46:54,654 Stage-1 map = 0%, reduce = 0%
2013-09-18 14:47:55,449 Stage-1 map = 0%, reduce = 0%
2013-09-18 14:48:56,193 Stage-1 map = 0%, reduce = 0%
2013-09-18 14:49:56,990 Stage-1 map = 0%, reduce = 0%
为什么map任务总是0%？它出什么问题了？有没有我没有配置的地方？
我在 datanode 日志文件中发现错误：
2013-09-18 15:18:27,415 INFO org.apache.zookeeper.ClientCnxn:
Opening socket connection to server datanode2/192.168.1.97:2181.
Will not attempt to authenticate using SASL (unknown error)
2013-09-18 15:18:27,417 WARN org.apache.zookeeper.ClientCnxn:
Session 0x0 for server null, unexpected error, closing socket
connection and attempting reconnect java.net.ConnectException:
Connection refused at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:692)
at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:350)
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1068)