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后面不加目录参数的话，默认当前用户的目录。/user/当前用户
$ hadoop fs -ls 16/05/19 10:40:10 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable Found 3 items drwxr-xr-x - yy yy 0 2016-04-24 08:00 .Trash drwx------ - yy yy 0 2016-05-06 06:00 .staging drwxr-xr-x - yy yy 0 2016-05-06 06:00 oozie-oozi
也可以加目录，显示指定目录的HDFS文件。
$ hadoop fs -ls /user/yy 16/05/19 10:44:07 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable Found 3 items drwxr-xr-x - yy yy 0 2016-04-24 08:00 /user/yy/.Trash drwx------ - yy yy 0 2016-05-06 06:00 /user/yy/.staging drwxr-xr-x - yy yy 0 2016-05-06 06:00 /user/yy/oozie-oozi
$ hadoop fs -mkdir upload
hadoop fs –rmr 可以删除文件夹/文件
hadoop fs -put pc/* upload
hadoop fs -get 可以把HDFS的文件下载到本机
hadoop fs -put upload/collect_20160518.txt /home/yy
$ hadoop fs -cat upload/collect_20160515.txt|head -10
查看分区： show partitions 表名;
external 外部分区表：
1）HDFS文件，要按分区存储，比如下面，分区为dt，对应的是2016-05-19下面的文件。
/user/yy/upload/wireless/2016-05-19
2）创建external表指向该存储（分区的上一层）
drop table if exists external_weblog_wireless; create external table external_weblog_wireless ( thedate string, time_stamp string, url_title string ) partitioned by (dt string) row format delimited fields terminated by ‘,‘ stored as textfile location ‘/user/yy/upload/wireless/‘;
3）添加新分区，指向分区目录
alter table external_weblog_wireless add partition (dt=‘2016-05-19‘) location ‘/user/yy/upload/wireless/2016-05-19‘;
4) 这种外部表分区存储，很适合增量数据。
external外部非分区表：
直接指向存储的最终location，建表即生成了数据表。
drop table if exists external_weblog_wireless; create external table external_weblog_wireless ( thedate string, time_stamp string, url_title string ) partitioned by (dt string) row format delimited fields terminated by ‘,‘ stored as textfile location ‘/user/yy/upload/wireless/2016-05-19‘;
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原文地址：http://www.cnblogs.com/skyEva/p/5508381.html
