加载数据到Hive表中

功能介绍

本小节介绍了如何使用HQL向已有的表employees_info中加载数据。从本节中可以掌握如何从本地文件系统、MRS集群中加载数据。以关键字LOCAL区分数据源是否来自本地。

样例代码

-- 从本地文件系统/opt/hive_examples_data/目录下将employee_info.txt加载进employees_info表中.
---- 用新数据覆盖原有数据 
LOAD DATA LOCAL INPATH '/opt/hive_examples_data/employee_info.txt' OVERWRITE INTO TABLE employees_info; 
---- 保留原有数据，将新数据追加到表中
LOAD DATA LOCAL INPATH '/opt/hive_examples_data/employee_info.txt' INTO TABLE employees_info;
 
-- 从HDFS上/user/hive_examples_data/employee_info.txt加载进employees_info表中. 
---- 用新数据覆盖原有数据
LOAD DATA INPATH '/user/hive_examples_data/employee_info.txt' OVERWRITE INTO TABLE employees_info; 
---- 保留原有数据，将新数据追加到表中
LOAD DATA INPATH '/user/hive_examples_data/employee_info.txt' INTO TABLE employees_info;
 

加载数据的实质是将数据复制到HDFS上指定表的目录下。

样例数据

表employees_info的数据如下：

1,Wang,R,8000.01,person&personal^Btype&income^Btax&0.05,Country1:City1,2014
3,Tom,D,12000.02,person&personal^Btype&income^Btax&0.09,Country2:City2,2014
4,Jack,D,24000.03,person&personal^Btype&income^Btax&0.05,Country3:City3,2014
6,Linda,D,36000.04,person&personal^Btype&income^Btax&0.05,Country4:City4,2014
8,Zhang,R,9000.05,person&personal^Btype&income^Btax&0.05,Country5:City5,2014

表employees_contact的数据如下：

1,135 XXXX XXXX,xxxx@xx.com
3,159 XXXX XXXX,xxxxx@xx.com.cn
4,186 XXXX XXXX,xxxx@xx.org
6,189 XXXX XXXX,xxxx@xxx.cn
8,134 XXXX XXXX,xxxx@xxxx.cn

表employees_info_extended的数据如下：

1,Wang,135 XXXX XXXX,xxxx@xx.com,R,8000.01,person&personal^Btype&income^Btax&0.05,Country1:City1,2014
3,Tom,159 XXXX XXXX,xxxxx@xx.com.cn,D,12000.02,person&personal^Btype&income^Btax&0.09,Country2:City2,2014
4,Jack,186 XXXX XXXX,xxxx@xx.org,D,24000.03,person&personal^Btype&income^Btax&0.05,Country3:City3,2014
6,Linda,189 XXXX XXXX,xxxx@xxx.cn,D,36000.04,person&personal^Btype&income^Btax&0.05,Country4:City4,2014
8,Zhang,134 XXXX XXXX,xxxx@xxxx.cn,R,9000.05,person&personal^Btype&income^Btax&0.05,Country5:City5,2014