为了查看表结构和数据方便使用客户端服务端模式访问hive
开启hive服务端（监听端口为10000）
[root@master apps]# hive-1.2.1/bin/hiveserver2开启服务端口后光标一直闪烁，表示开启
客户端连接hive服务端并进行操作
hive当做客户端(在另一台机器上操作)
注： Enter username for jdbc:hive2://master.hadoop:10000:（此处输入启动服务端的用户）
Enter password for jdbc:hive2://master.hadoop:10000:（此处没配密码，直接回车跳过）
具体操作如下：
[root@slave1 apps]# cd hive-1.2.1/
[root@slave1 hive-1.2.1]# bin/beeline
Beeline version 1.2.1 by Apache Hivebeeline> !connect jdbc:hive2://master.hadoop:10000Connecting to jdbc:hive2://master.hadoop:10000
Enter username for jdbc:hive2://master.hadoop:10000: root
Enter password for jdbc:hive2://master.hadoop:10000: Connected to: Apache Hive (version 1.2.1)
Driver: Hive JDBC (version 1.2.1)
Transaction isolation: TRANSACTION_REPEATABLE_READ
0: jdbc:hive2://master.hadoop:10000> show databases;
+----------------+--+
| database_name |
+----------------+--+
| default |
| mydb |
+----------------+--+
2 rows selected (3.776 seconds)
0: jdbc:hive2://master.hadoop:10000> use mydb;
No rows affected (0.352 seconds)
0: jdbc:hive2://master.hadoop:10000> show tables;
+-----------+--+
| tab_name |
+-----------+--+
| t_1 |
| t_1_like |
| t_1_son |
| t_2 |
+-----------+--+
4 rows selected (0.236 seconds)
0: jdbc:hive2://master.hadoop:10000>
hive DDL操作
1、创建内部表，该表的目录有hive自动创建
create table t_1(id int, name string,password string)
row format delimited
fields terminated by ',';0: jdbc:hive2://master.hadoop:10000> create table t_1(id int, name string,password string)
0: jdbc:hive2://master.hadoop:10000> row format delimited
0: jdbc:hive2://master.hadoop:10000> fields terminated by ',';
No rows affected (1.671 seconds)
0: jdbc:hive2://master.hadoop:10000> show tables;
+-----------+--+
| tab_name |
+-----------+--+
| t_1 |
+-----------+--+
1 row selected (0.104 seconds)2、创建外部表，可以指定文件目录
create external table t_2(id int, name string,password string)
row format delimited
fields terminated by ','
location '/aa/bb';0: jdbc:hive2://master.hadoop:10000> create external table t_2(id int, name string,password string)
0: jdbc:hive2://master.hadoop:10000> row format delimited
0: jdbc:hive2://master.hadoop:10000> fields terminated by ','
0: jdbc:hive2://master.hadoop:10000> location '/aa/bb';
No rows affected (4.267 seconds)
0: jdbc:hive2://master.hadoop:10000> show tables;
+-----------+--+
| tab_name |
+-----------+--+
| t_1 |
| t_2 |
+-----------+--+
2 rows selected (0.363 seconds)
0: jdbc:hive2://master.hadoop:10000> 1）
内部表的目录有hive创建在默认的目录下面：/user/hive/warehouse/......
外部表的目的目录有用户自己建表是指定：location '/位置'
2）
drop一个内部表时，表的元信息和表数据目录都会被删掉
drop一个外部表时，只删除表的元信息，表的数据目录不会删除
外部表的意义：通常一个数据仓库系统，数据都是有别的系统产生的，为了方便映射，就可以在hive
中用外部表映射，并且就算hive中的表被删除了，但是目录还在，不会影响到继续使用该目录的系统。
3、导入数据
1）导入本地文件到hive：(该文件需位于运行hive的机器上在这里为master.hadoop)
load data local inpath '/root/a.txt' into table t_1;
具体操作如下：
0: jdbc:hive2://master.hadoop:10000> load data local inpath '/root/a.txt' into table t_1;INFO : Loading data to table mydb.t_1 from file:/root/a.txt
INFO : Table mydb.t_1 stats: [numFiles=1, totalSize=45]
No rows affected (0.911 seconds)
0: jdbc:hive2://master.hadoop:10000> select * from t_1;
+---------+-----------+---------------+--+
| t_1.id | t_1.name | t_1.password |
+---------+-----------+---------------+--+
| 1 | user1 | 123123 |
| 2 | user2 | 123123 |
| 3 | user3 | 123123 |
+---------+-----------+---------------+--+
3 rows selected (0.289 seconds)
0: jdbc:hive2://master.hadoop:10000>
load data inpath '/a.txt' into table t_1;（此操作会将hdfs下的该文件直接移走到表目录中）
具体操作如下：
查看hdfs下的文件
[root@master ~]# hadoop fs -ls /
Found 4 items
-rw-r--r-- 2 root supergroup 45 2018-07-08 02:47 /a.txt
drwxr-xr-x - root supergroup 0 2018-07-07 16:40 /root
drwx-wx-wx - root supergroup 0 2018-07-07 16:05 /tmp
drwxr-xr-x - root supergroup 0 2018-07-07 16:36 /user
[root@master ~]# 上传a.txt 到hive
0: jdbc:hive2://master.hadoop:10000> load data inpath '/a.txt' into table t_1;INFO : Loading data to table mydb.t_1 from hdfs://ns/a.txt
INFO : Table mydb.t_1 stats: [numFiles=2, totalSize=90]
No rows affected (0.986 seconds)
0: jdbc:hive2://master.hadoop:10000> select * from t_1;
+---------+-----------+---------------+--+
| t_1.id | t_1.name | t_1.password |
+---------+-----------+---------------+--+
| 1 | user1 | 123123 |
| 2 | user2 | 123123 |
| 3 | user3 | 123123 |
| 1 | user1 | 123123 |
| 2 | user2 | 123123 |
| 3 | user3 | 123123 |
+---------+-----------+---------------+--+
6 rows selected (0.435 seconds)
0: jdbc:hive2://master.hadoop:10000> 再次查看HDFS文件目录
[root@master ~]# hadoop fs -ls /
Found 3 items
drwxr-xr-x - root supergroup 0 2018-07-07 16:40 /root
drwx-wx-wx - root supergroup 0 2018-07-07 16:05 /tmp
drwxr-xr-x - root supergroup 0 2018-07-07 16:36 /user
[root@master ~]#
create table t_1_son
as
select * from t_1;create table t_1_like like t_1;给其插入数据
insert into table t_1_like
select
id,name,password
from t_1;4、导出数据：
导出到hdfs
insert overwrite directory '/root/aa/bb'
select * from t_1;导出到本地
insert overwrite local directory '/root/aa/bb'
select * from t_1;