Hive 练习操作2 文件保存在HDFS , HIVE 数据仓库建表

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步骤1 :拷贝数据文件 HDFS
[root@master /]# hadoop fs -put /opt/exercise/names.txt /user/root/names.txt


[root@master /]# hadoop fs -ls /user/root/names.txt
-rw-r--r-- 2 root supergroup 78 2017-08-28 15:17 /user/root/names.txt
You have new mail in /var/spool/mail/root

步骤2 : 新建文件夹
[root@master /]# hadoop fs -mkdir /user/root/hivedemo


步骤3:新建表, 并指定数据存储位置在 /user/root/hivedemo


hive (default)> create table names(id int , name string)
> ROW FORMAT delimited fields terminated by '\t'
> LOCATION '/USER/ROOT/hivedemo';
OK
Time taken: 3.438 seconds

步骤4:把数据导入hive 外部表的names 表中

hive (default)> load data inpath '/user/root/names.txt' into table names;
Loading data to table default.names
Table default.names stats: [numFiles=0, totalSize=0]
OK
Time taken: 1.661 seconds

步骤5: 查询

hive (default)> select * from names;
OK
names.id names.name
0 Rich
1 Barry
2 George
3 Ulf
4 Danielle
5 Tom
6 manish
7 Brian
8 Mark
Time taken: 1.38 seconds, Fetched: 9 row(s)

hive (default)> dfs -ls hivedemo;
hive (default)> dfs -ls /user/hive/warehouse;
Found 2 items
-rw-r--r-- 2 root supergroup 989239 2017-08-24 15:03 /user/hive/warehouse/employees
drwxr-xr-x - root supergroup 0 2017-08-24 15:08 /user/hive/warehouse/people_visits

如果drop table names 但是HDFS 里面并不会删除