hive基本操作与应用

通过hadoop上的hive完成WordCount

start-all.sh

　　

启动hadoop

hdfs dfs -mkdir songinput
hdfs dfs -ls /user/hadoop

Hdfs上创建文件夹

cd ~/hadoop
ls

上传文件至hdfs

hdfs dfs -put ./songs.txt songinput
hdfs dfs -ls /user/hadoop/songinput

启动Hive

hive

创建原始文档表

create table docs(line string);<br>show tables;

导入文件内容到表docs并查看

load data inpath '/user/hadoop/songinput/songs.txt' overwrite into table docs;<br>select * from docs;

用HQL进行词频统计，结果放在表word_count里

create table word_count as select word,count(1) from (select explode(split(line,' ')) as word from docs) word group by word;

查看统计结果

select * from word_count;