搭建Hadoop2.7.3+Hive2.1.1及MySQL(配置Hive+MySQL+Connector）(三)

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搭建Hadoop2.7.3+Hive2.1.1及MySQL(配置Hive+Hadoop）(二)

准备工作下载最新连接器地址

https://dev.mysql.com/downloads/connector/j/

例子：下载mysql-connector-java-5.1.41.tar

1、解压连接器connector文件

1.1、解压

[[email protected] Software]# tar xzfmysql-connector-java-5.1.41.tar.gz
[[email protected] Software]# cd mysql-connector-java-5.1.41/

1.2、查看文件夹

[[email protected]]# ll

1.3、Copy到hive/lib路径下

[[email protected] Software]# cpmysql-connector-java-5.1.41/mysql-connector-java-5.1.41-bin.jar/usr/hive/lib/mysql-connector-java-5.1.41-bin.jar

2、登陆MySQL创建数据库:hive_db（注意配置hive-site.xml时有指定）

2.1、用户名:root 密码:password，另开一个终端登陆MySQL,创建数据库hive_db

[[email protected] hive]# mysql -u root -ppassword

mysql> create database hive_db;

3、改配置文件hive-site.xml

以下只列出改动的配置项，其它保留默认

<configuration>
	<property>
		<name>hive.metastore.warehouse.dir</name>
		<value>/usr/hive/warehouse</value>
		<description>location of default database for the warehouse</description>
	</property>
	<property>
		<name>hive.metastore.local</name>
		<value>true</value>
		<description>Use false if a production metastore server is used</description>
	</property>
	<property>
		<name>hive.exec.scratchdir</name>
		<value>/tmp/hive</value>
		<description>HDFS root scratch dir for Hive jobs which gets created with write all (733) permission. For each connecting user, an HDFS scratch dir: ${hive.exec.scratchdir}/<username> is created, with ${hive.scratch.dir.permission}.</description>
	</property>
	<property>
		<name>javax.jdo.option.ConnectionURL</name>
		<value>jdbc:mysql://localhost:3306/hive_db?createDatabaseIfNoExist=true</value>
		<description> Roy
      JDBC connect string for a JDBC metastore.
      To use SSL to encrypt/authenticate the connection, provide database-specific SSL flag in the connection URL.
      For example, jdbc:postgresql://myhost/db?ssl=true for postgres database.
    </description>
	</property>
	<property>
		<name>javax.jdo.option.ConnectionDriverName</name>
		<value>com.mysql.jdbc.Driver</value>
		<description>User-Defined(Roy) Driver class name for a JDBC metastore</description>
	</property>
	<property>
		<name>javax.jdo.option.ConnectionUserName</name>
		<value>root</value>
		<description>User-defined(Roy)Username to use against metastore database</description>
	</property>
	<property>
		<name>javax.jdo.option.ConnectionPassword</name>
		<value>password</value>
		<description>User-defined(Roy)password to use against metastore database</description>
	</property>
</configuration>

4、使用schematool初始化

[[email protected] hive]# schematool -dbType mysql  -initSchema

--显示成功

schemaTool completed

5、启动hive服务端程序

5.1、启动hive服务端

[[email protected] hive]# hive --servicemetastore &

--屏幕提示信息不显示时，按ctrl+c退出

5.2、查看进程信息

[[email protected] hive]# jps

--显示进程信息多了（RunJar）

51280 Jps
5985 SecondaryNameNode
6226 ResourceManager
45766 DataNode
5753 NameNode
51194 RunJar
6348 NodeManager

5.3、有需要时，可启动hive  远程服务 (端口号10000)

[[email protected] hive]# hive --servicehiveserver &

6、测试环境配置是否成功

6.1、准备导入文本文件/root/桌面/Test/wc-in/a.txt

格式：

1,h
2,i
3,v
4,e

6.2、登陆hive成功后，测试创建表

[email protected] hadoop]# hive

6.2.1、创建表及指定逗号（，）为分隔符

hive> create table a(id int,name string)
   > row format delimited fields terminated by ‘,‘;

--显示信息

OK
Time taken: 0.288 seconds

6.2.2、导入文件a.txt

hive> load data local inpath ‘/root/桌面/Test/wc-in/a.txt‘ into table a;

--显示信息

Loading data to table default.a
OK
Time taken: 0.763 seconds

6.2.3、查看效果

hive> select * from a;

--显示信息

OK
1     h
2     i
3     v
4     e
Time taken: 0.309 seconds, Fetched: 4row(s)

6.3、在Hive内使用dfs命令

6.3.1、查看a表dfs存储路径

hive> dfs -ls /usr/hive/warehouse/a;

--显示信息

Found 1 items
-rw-r--r--  1 root supergroup         16 2017-03-08 17:46/usr/hive/warehouse/a/a.txt

6.3.2、查看文件内容

hive> dfs -cat /usr/hive/warehouse/a/*;

--显示信息

1,h
2,i
3,v
4,e

7、登陆MySQL查看创建表

[[email protected] conf]# mysql -u root -ppassword

mysql> use hive_db;
mysql> select TBL_ID, CREATE_TIME,DB_ID, OWNER, TBL_NAME,TBL_TYPE from TBLS;

--显示信息

+--------+-------------+-------+-------+----------+---------------+
| TBL_ID | CREATE_TIME | DB_ID | OWNER |TBL_NAME | TBL_TYPE      |
+--------+-------------+-------+-------+----------+---------------+
|    37 |  1488966386 |     1 | root | a        | MANAGED_TABLE |
+--------+-------------+-------+-------+----------+---------------+
1 row in set (0.03 sec)

8、在hdfs查看生成文件（同上步骤[6.3]）

8.1、查看a表存储路径

[[email protected] hadoop]# hdfs dfs -ls/usr/hive/warehouse/a

--显示信息

Found 1 items
-rw-r--r--  1 root supergroup         162017-03-08 17:46 /usr/hive/warehouse/a/a.txt

8.2、查看内容

[[email protected] hadoop]# hdfs dfs -cat  /usr/hive/warehouse/a/*

--显示信息

1,h
2,i
3,v
4,e

常见问题处理：

1、启动hive时报错

[[email protected] hive]# hive

--显示报错信息

Caused by:org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.hdfs.server.namenode.SafeModeException):Cannot create directory /tmp/hive/root/24f1d91f-f32b-47e1-824d-ba26b02bd13e.Name node is in safe mode.

原因：hadoop为安全模式

--解决方法：

关闭安全模式

[[email protected] hadoop]# hadoop dfsadmin-safemode leave

--显示信息

DEPRECATED: Use of this script to executehdfs command is deprecated.
Instead use the hdfs command for it.

Safe mode is OFF

2、在导入数据时出错信息

hive> load data local inpath ‘/root/桌面/Test/wc-in/a.txt‘ into table a;

--显示报错信息

FAILED: Execution Error, return code 1 fromorg.apache.hadoop.hive.ql.exec.MoveTask.org.apache.hadoop.ipc.RemoteException(java.io.IOException): File/usr/hive/warehouse/a/a_copy_2.txt could only be replicated to 0 nodes insteadof minReplication (=1).  There are 0datanode(s) running and no node(s) are excluded in this operation.

原因：hadoop没有启动datanote

解决方法：

[[email protected] hive]# start-dfs.sh
[[email protected] hive]# jps

--显示信息

51152 Jps
5985 SecondaryNameNode
6226 ResourceManager
45766 DataNode
5753 NameNode
6348 NodeManager