hive基本操作与应用
通过hadoop上的hive完成WordCount
启动hadoop
ssh localhost cd /usr/local/hadoop ./sbin/start-dfs.sh cd /usr/local/hive/lib service mysql start start-all.sh
Hdfs上创建文件夹
hdfs dfs -mkdir wcinput
hdfs dfs -ls /user/hadoop
上传文件至hdfs
hdfs dfs -put ~/123.txt wcinput
hdfs dfs -ls /user/hadoop/wcinput
启动Hive
hive
创建原始文档表
create table docs(line string)
导入文件内容到表docs并查看
load data inpath '/user/hadoop/wcinput/123.txt' overwrite into table docs
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) as count from (select explode(split(line," ")) as word from docs) word group by word order by word;
查看统计结果
show tables;
select * from word_count;