hadoop2-hive的安装和测试

在安装和测试hive之前，我们需要把Hadoop的所有服务启动

在安装Hive之前，我们需要安装mysql数据库

--mysql的安装 - (https://segmentfault.com/a/1190000003049498)
--检测系统是否自带安装mysql
yum list installed | grep mysql

--删除系统自带的mysql及其依赖
yum -y remove mysql-libs.x86_64


--给CentOS添加rpm源，并且选择较新的源
wget dev.mysql.com/get/mysql-community-release-el6-5.noarch.rpm
yum localinstall mysql-community-release-el6-5.noarch.rpm
yum repolist all | grep mysql
yum-config-manager --disable mysql55-community
yum-config-manager --disable mysql56-community
yum-config-manager --enable mysql57-community-dmr
yum repolist enabled | grep mysql

--安装mysql 服务器
yum install mysql-community-server

--启动mysql
service mysqld start

--查看mysql是否自启动,并且设置开启自启动
chkconfig --list | grep mysqld
chkconfig mysqld on

--查找初始化密码
grep 'temporary password' /var/log/mysqld.log

--mysql安全设置
mysql_secure_installation

--启动mysql
service mysqld start
--登录
mysql –u root –p
--设置的密码
!QAZ2wsx3edc

--开通远程访问
grant all on *.* to root@'%' identified by '!QAZ2wsx3edc';

select * from mysql.user;

--让node1也可以访问
grant all on *.* to root@'node1' identified by '!QAZ2wsx3edc';

--创建hive数据库,后面要用到，hive不会 自动创建
create database hive;

安装和配置Hive

--安装Hive
cd ~
tar -zxvf apache-hive-0.13.1-bin.tar.gz

--创建软链
ln -sf /root/apache-hive-0.13.1-bin /home/hive

--修改配置文件
cd /home/hive/conf/

cp -a hive-default.xml.template hive-site.xml

--启动Hive
cd /home/hive/bin/

./hive

--退出hive
quit;

--修改配置文件
cd /home/hive/conf/

vi hive-site.xml

--以下需要修改的地方
<property>
  <name>javax.jdo.option.ConnectionURL</name>
  <value>jdbc:mysql://node1/hive</value>
  <description>JDBC connect string for a JDBC metastore</description>
</property>

<property>
  <name>javax.jdo.option.ConnectionDriverName</name>
  <value>com.mysql.jdbc.Driver</value>
  <description>Driver class name for a JDBC metastore</description>
</property>
<property>
  <name>javax.jdo.option.ConnectionUserName</name>
  <value>root</value>
  <description>username to use against metastore database</description>
</property>

<property>
  <name>javax.jdo.option.ConnectionPassword</name>
  <value>!QAZ2wsx3edc</value>
  <description>password to use against metastore database</description>
</property>

:wq

添加mysql驱动

--拷贝mysql驱动到/home/hive/lib/
cp -a mysql-connector-java-5.1.23-bin.jar /home/hive/lib/

在这里我写了一个生成文件的java文件

GenerateTestFile.java

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.util.Random;

/**
 * @author Hongwei
 * @created 31 Oct 2018
 */
public class GenerateTestFile {

    public static void main(String[] args) throws Exception{
        int num = 20000000;
        File writename = new File("/root/output1.txt");
        System.out.println("begin");
        writename.createNewFile();
        BufferedWriter out = new BufferedWriter(new FileWriter(writename));
        StringBuilder sBuilder = new StringBuilder();
        for(int i=1;i<num;i++){
            Random random = new Random();
            sBuilder.append(i).append(",").append("name").append(i).append(",")
.append(random.nextInt(50)).append(",").append("Sales").append("\n");
        }
        System.out.println("done........");
        
        out.write(sBuilder.toString());
        out.flush();
        out.close();
    }
}

编译和运行文件：

cd
javac GenerateTestFile.java
java GenerateTestFile

最终就会生成/root/output1.txt文件，为上传测试文件做准备。

启动Hive

--启动hive
cd /home/hive/bin/
./hive

创建t_tem2表

create table t_emp2(
id int,
name string,
age int,
dept_name string
)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ',';

输出结果：

hive> create table t_emp2(
    > id int,
    > name string,
    > age int,
    > dept_name string
    > )
    > ROW FORMAT DELIMITED
    > FIELDS TERMINATED BY ',';
OK
Time taken: 0.083 seconds

上传文件

load data local inpath '/root/output1.txt' into table t_emp2;

输出结果：

hive> load data local inpath '/root/output1.txt' into table t_emp2;
Copying data from file:/root/output1.txt
Copying file: file:/root/output1.txt
Loading data to table default.t_emp2
Table default.t_emp2 stats: [numFiles=1, numRows=0, totalSize=593776998, rawDataSize=0]
OK
Time taken: 148.455 seconds

测试，查看t_temp2表里面所有记录的总条数：

hive> select count(*) from t_emp2;
Total jobs = 1
Launching Job 1 out of 1
Number of reduce tasks determined at compile time: 1
In order to change the average load for a reducer (in bytes):
  set hive.exec.reducers.bytes.per.reducer=<number>
In order to limit the maximum number of reducers:
  set hive.exec.reducers.max=<number>
In order to set a constant number of reducers:
  set mapreduce.job.reduces=<number>
Starting Job = job_1541003514112_0002, Tracking URL = http://node1:8088/proxy/application_1541003514112_0002/
Kill Command = /home/hadoop-2.5/bin/hadoop job  -kill job_1541003514112_0002
Hadoop job information for Stage-1: number of mappers: 3; number of reducers: 1
2018-10-31 09:41:49,863 Stage-1 map = 0%,  reduce = 0%
2018-10-31 09:42:26,846 Stage-1 map = 33%,  reduce = 0%, Cumulative CPU 33.56 sec
2018-10-31 09:42:47,028 Stage-1 map = 44%,  reduce = 0%, Cumulative CPU 53.03 sec
2018-10-31 09:42:48,287 Stage-1 map = 56%,  reduce = 0%, Cumulative CPU 53.79 sec
2018-10-31 09:42:54,173 Stage-1 map = 67%,  reduce = 0%, Cumulative CPU 56.99 sec
2018-10-31 09:42:56,867 Stage-1 map = 78%,  reduce = 0%, Cumulative CPU 57.52 sec
2018-10-31 09:42:58,201 Stage-1 map = 100%,  reduce = 0%, Cumulative CPU 58.44 sec
2018-10-31 09:43:16,966 Stage-1 map = 100%,  reduce = 100%, Cumulative CPU 60.62 sec
MapReduce Total cumulative CPU time: 1 minutes 0 seconds 620 msec
Ended Job = job_1541003514112_0002
MapReduce Jobs Launched: 
Job 0: Map: 3  Reduce: 1   Cumulative CPU: 60.62 sec   HDFS Read: 593794153 HDFS Write: 9 SUCCESS
Total MapReduce CPU Time Spent: 1 minutes 0 seconds 620 msec
OK
19999999
Time taken: 105.013 seconds, Fetched: 1 row(s)

查询表中age=20的记录总条数：

hive> select count(*) from t_emp2 where age=20;
Total jobs = 1
Launching Job 1 out of 1
Number of reduce tasks determined at compile time: 1
In order to change the average load for a reducer (in bytes):
  set hive.exec.reducers.bytes.per.reducer=<number>
In order to limit the maximum number of reducers:
  set hive.exec.reducers.max=<number>
In order to set a constant number of reducers:
  set mapreduce.job.reduces=<number>
Starting Job = job_1541003514112_0003, Tracking URL = http://node1:8088/proxy/application_1541003514112_0003/
Kill Command = /home/hadoop-2.5/bin/hadoop job  -kill job_1541003514112_0003
Hadoop job information for Stage-1: number of mappers: 3; number of reducers: 1
2018-10-31 09:44:28,452 Stage-1 map = 0%,  reduce = 0%
2018-10-31 09:44:45,102 Stage-1 map = 11%,  reduce = 0%, Cumulative CPU 5.54 sec
2018-10-31 09:44:49,318 Stage-1 map = 33%,  reduce = 0%, Cumulative CPU 7.63 sec
2018-10-31 09:45:14,247 Stage-1 map = 44%,  reduce = 0%, Cumulative CPU 13.97 sec
2018-10-31 09:45:15,274 Stage-1 map = 67%,  reduce = 0%, Cumulative CPU 14.99 sec
2018-10-31 09:45:41,594 Stage-1 map = 100%,  reduce = 0%, Cumulative CPU 18.7 sec
2018-10-31 09:45:50,973 Stage-1 map = 100%,  reduce = 100%, Cumulative CPU 26.08 sec
MapReduce Total cumulative CPU time: 26 seconds 80 msec
Ended Job = job_1541003514112_0003
MapReduce Jobs Launched: 
Job 0: Map: 3  Reduce: 1   Cumulative CPU: 33.19 sec   HDFS Read: 593794153 HDFS Write: 7 SUCCESS
Total MapReduce CPU Time Spent: 33 seconds 190 msec
OK
399841
Time taken: 98.693 seconds, Fetched: 1 row(s)

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