欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  数据库

Alex的Hadoop菜鸟教程:第7课Sqoop2导入教程

程序员文章站 2022-05-21 08:06:21
...

具体的安装和jdbc的驱动准备你们看第6课。现在我用一个例子讲解sqoop2的具体使用方法 数据准备 有一个mysql的表叫worker,里面有三条数据,我们要将其导入hadoop 这是建表语句 CREATE TABLE `workers` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` varch

具体的安装和jdbc的驱动准备你们看第6课。现在我用一个例子讲解sqoop2的具体使用方法

数据准备

有一个mysql的表叫worker,里面有三条数据,我们要将其导入hadoop

这是建表语句

CREATE TABLE `workers` (  
  `id` int(11) NOT NULL AUTO_INCREMENT,  
  `name` varchar(20) NOT NULL,  
  PRIMARY KEY (`id`)  
) ENGINE=MyISAM  DEFAULT CHARSET=utf8; 

插入三条数据

insert into workers (name) values ('jack');
insert into workers (name) values ('vicky');
insert into workers (name) values ('martin');

接下来我们使用sqoop客户端进行导入工作

导入数据

建立数据库连接

$ sqoop2
Sqoop home directory: /usr/lib/sqoop2
Sqoop Shell: Type 'help' or '\h' for help.

sqoop:000> create connection --cid 1

这句话的意思是建立一个id为1的连接,然后sqoop会让你输入一些必要参数

Creating connection for connector with id 1
Please fill following values to create new connection object
Name: First connection

Configuration configuration
JDBC Driver Class: com.mysql.jdbc.Driver
JDBC Connection String: jdbc:mysql://mysql.server/database
Username: sqoop
Password: *****
JDBC Connection Properties:
There are currently 0 values in the map:
entry#

Security related configuration options
Max connections: 0
New connection was successfully created with validation status FINE and persistent id 1

记得把 jdbc:mysql://mysql.server/database 替换成你真实的数据库连接

建立job

建立一个id为1的job,类型是 import
sqoop:000> create job --xid 1 --type import

接下来sqoop会让你输入需要的参数,只需要输入job的名字和Table name就好了,还有几个存储选项都选0,其他直接回车
Creating job for connection with id 1
Please fill following values to create new job object
Name: First job

Database configuration
Table name: workers
Table SQL statement:
Table column names:
Partition column name:
Boundary query:

Output configuration
Storage type:
  0 : HDFS
Choose: 0
Output format: 
  0 : TEXT_FILE
  1 : SEQUENCE_FILE
Choose: 0
Compression format: 
  0 : NONE
  1 : DEFAULT
  2 : DEFLATE
  3 : GZIP
  4 : BZIP2
  5 : LZO
  6 : LZ4
  7 : SNAPPY
Choose: 0
Output directory: /user/jarcec/users
New job was successfully created with validation status FINE and persistent id 1

执行任务

用start job命令去执行这个任务,用--jid来传入任务id
sqoop:000> start job --jid 1
Submission details
Job ID: 1
Server URL: http://localhost:12000/sqoop/
Created by: root
Creation date: 2014-11-26 16:41:30 CST
Lastly updated by: root
External ID: job_1406097234796_0006
	N/A
2014-11-26 16:41:30 CST: BOOTING  - Progress is not available

检查结果

再打开一个ssh终端,然后用hdfs的命令查看结果
$ hdfs dfs -ls /user/jarcec/workers/
Found 3 items
-rw-r--r--   2 sqoop2 supergroup          0 2014-11-26 16:42 /user/jarcec/workers/_SUCCESS
-rw-r--r--   2 sqoop2 supergroup          9 2014-11-26 16:41 /user/jarcec/workers/part-m-00000
-rw-r--r--   2 sqoop2 supergroup         21 2014-11-26 16:42 /user/jarcec/workers/part-m-00001

可以看到有三个结果文件被生成,然后我们cat看下文件的内容
$ hdfs dfs -cat /user/jarcec/workers/part-m-00000
1,'jack'
$ hdfs dfs -cat /user/jarcec/workers/part-m-00001
2,'vicky'
3,'martin'

今天写到这里,下节课讲讲导出