Hiveserver2的使用

hive的版本是hive-2.1.1

日志放在哪？

Hive中的日志分为两种
1. 系统日志，记录了hive的运行情况，错误状况。
2. Job 日志，记录了Hive 中job的执行的历史过程。

系统日志存储在什么地方呢 ？
在hive/conf/ hive-log4j.properties 文件中记录了Hive日志的存储情况，
默认的存储情况：

hive.root.logger=WARN,DRFA
hive.log.dir=/tmp/${user.name} # 默认的存储位置
hive.log.file=hive.log  # 默认的文件名

Job日志又存储在什么地方呢 ？

//Location of Hive run time structured log file
    HIVEHISTORYFILELOC("hive.querylog.location", "/tmp/" + System.getProperty("user.name")),
默认存储与 /tmp/{user.name}目录下。

注意：在建立JDBC连接时候的连接是 hive2,hive从此以后的hiveserver是hive2了

出现了错误：User: hadoop is not allowed to impersonate anonymous

解决方案

<property>
    <name>hadoop.proxyuser.root.hosts</name>
    <value>*</value>

</property>
<property>
    <name>hadoop.proxyuser.root.groups</name>
    <value>*</value>

</property>

JDBCUtil.java

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class JDBCUtils {
	private static String driver = "org.apache.hive.jdbc.HiveDriver";
	private static String url = "jdbc:hive2://192.168.56.100:10000/default";
	
	
	//注册驱动
	static {
		try {
			Class.forName(driver);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}
	//获取连接
	public static Connection getConnection(){
		try {
			return DriverManager.getConnection(url,"root","root");
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}
	
	//释放资源
	public static void release(Connection conn,Statement st,ResultSet rs){
		if(rs != null){
			try {
				rs.close();	
			} catch (Exception e) {
				// TODO: handle exception
				e.printStackTrace();
			}finally {
				rs = null;
			}

		}
		if(st != null){
			try {
				st.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}finally {
				st = null;
			}
		}
		if(conn != null){
			try {
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}finally {
				conn = null;
			}
		}
	}	
			
}

HiveJDBCDemon.java

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;

public class HIveJDBCDemon {
	public static void main(String[] args) {
		Connection conn = null;
		Statement st = null;
		ResultSet rs = null;
		String sql = "select * from word_counts";
		
		
		try {
			//获取连接
			conn = JDBCUtils.getConnection();
			
			System.out.println(conn);
			//创建运行环境
			st = conn.createStatement();
			//运行HSQL
			rs = st.executeQuery(sql);
			
			//处理数据
			while(rs.next()){
			
				String word = rs.getString(1);
				int count = rs.getInt(2);
				System.out.println(word + "\t" + count);
			}
		} catch (Exception e) {
			// TODO: handle exception
			e.printStackTrace();
		}finally {
			JDBCUtils.release(conn, st, rs);
		}
	}
}

//下面是hadoop 官网的详解

http://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-common/Superusers.html

Configurations

You can configure proxy user using properties hadoop.proxyuser.$superuser.hosts along with either or both of hadoop.proxyuser.$superuser.groups and hadoop.proxyuser.$superuser.users.

By specifying as below in core-site.xml, the superuser named super can connect only from host1 and host2 to impersonate a user belonging to group1 and group2.

   <property>
     <name>hadoop.proxyuser.super.hosts</name>
     <value>host1,host2</value>
   </property>
   <property>
     <name>hadoop.proxyuser.super.groups</name>
     <value>group1,group2</value>
   </property>
If these configurations are not present, impersonation will not be allowed and connection will fail.

If more lax security is preferred, the wildcard value * may be used to allow impersonation from any host or of any user. For example, by specifying as below in core-site.xml, user named oozie accessing from any host can impersonate any user belonging to any group.

  <property>
    <name>hadoop.proxyuser.oozie.hosts</name>
    <value>*</value>
  </property>
  <property>
    <name>hadoop.proxyuser.oozie.groups</name>
    <value>*</value>
  </property>
The hadoop.proxyuser.$superuser.hosts accepts list of ip addresses, ip address ranges in CIDR format and/or host names. For example, by specifying as below, user named super accessing from hosts in the range 10.222.0.0-15 and 10.113.221.221 can impersonate user1 and user2.

   <property>
     <name>hadoop.proxyuser.super.hosts</name>
     <value>10.222.0.0/16,10.113.221.221</value>
   </property>
   <property>
     <name>hadoop.proxyuser.super.users</name>
     <value>user1,user2</value>
   </property>