Use of HiveServer2 with Beeline & Hive JDBC Programming

Use of Hiveserver2&beeline Overview

Url:
Https://cwiki.apache.org/confluence/display/Hive/HiveServer2+Clients

Hive is just a client, and in production it is not necessary to deploy the cluster

There are several major classes of hive clients:
-Hive
-WebUI: Operation of hive table via Hue/zeppelin
- use of JDBC HiveServer2

The concept of Hiveserver:
Start a server on the hive machine: The client can access it via IP + port
After that, there are a lot of clients that can connect to the server and work on it.
Can be connected in a JDBC, ODBC, Beeline Way

Start HiveServer2:

$>CD $HIVE _home/bin
$>./hiveserver2

use of Beeline

Start Beeline:

##-n Specify the name of the machine login, the current machine login user name
##-u Specify a connection string
# #每成功运行一个命令, hiveserver2 start the window, as long as the launch Beeline in the window to execute a successful command, Another window prints an OK
# #如果命令错误, hiveserver2 that window throws an exception
$>./beeline-u jdbc:hive2://hadoop003:10000/default-n Hadoop

Operating effect:

set the port yourself, using HiveServer2 and Beeline

To set the port for Hiveserver:

$>./hiveserver2--hiveconf hive.server2.thrift.port=4444

To start the Beeline client:

$>./beeline-u jdbc:hive2://hadoop003:4444/default-n Hadoop

Hive JDBC Programming

Note the point:
JDBC is the way clients are accessed, so you need to start a server that is HiveServer2

To build a project using MAVEN, the Pom.xml file looks like this:

<project xmlns= "http://maven.apache.org/POM/4.0.0" xmlns:xsi= "Http://www.w3.org/2001/XMLSchema-instance" xsi: schemalocation= "http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" > < Modelversion>4.0.0</modelversion> <groupId>com.zhaotao.bigdata</groupId> <artifactId> hive-train</artifactid> <version>1.0</version> <packaging>jar</packaging> <name& gt;hive-train</name> <url>http://maven.apache.org</url> <properties> <project.build.so Urceencoding>utf-8</project.build.sourceencoding>  
 Program: 
 

Package com.zhaotao.bigdata.hive;

Import java.sql.*;
 /** * Hive JDBC JAVA API Access * CRUD operation * Created by Tao on 2017/10/7.

    */public class Hivejdbc {private static String drivername = "Org.apache.hive.jdbc.HiveDriver"; /** * @param args * @throws SQLException */public static void main (string[] args) throws SQLException
        {try {class.forname (drivername);
            } catch (ClassNotFoundException e) {e.printstacktrace ();
        System.exit (1); }//replace "Hive" here with the name of the user the queries should run as Connection con = drivermanage
        R.getconnection ("Jdbc:hive2://192.168.26.133:4444/default", "Root", "" ");

        Statement stmt = Con.createstatement ();
        Used to test the creation of a new table String tableName = "testhivedrivertable";

        Data for querying an existing EMP//String tableName = "EMP";
     If the following actions are performed under the Windows operating system, the source of the permissions issue//problem is due to the fact that the permissions of the files in HDFs are not sufficient for users of Windows to operate   Workaround: Modify permissions//delete table Stmt.execute ("drop table if exists" + tableName);

        CREATE TABLE Stmt.execute ("CREATE TABLE" + TableName + "(key int, value string)");
Display table name//String sql = "Show tables '" + tableName + "'";
System.out.println ("Running:" + sql);
ResultSet res = stmt.executequery (SQL);  if (Res.next ()) {//System.out.println (res.getstring (1));//}//Table descriptor//SQL
= "Describe" + tableName;
System.out.println ("Running:" + sql);
res = stmt.executequery (SQL);

        while (Res.next ()) {//System.out.println (res.getstring (1) + "\ T" + res.getstring (2));//}
Load data into hive Table//String filepath = "/opt/data/emp.txt";
sql = "Load data local inpath '" + filepath + "' into table" + tableName;
System.out.println ("Running:" + sql);

        Stmt.execute (SQL); Querying the Hive table for data//sql = "SelecT * from "+ tableName;
System.out.println ("Running:" + sql);
res = stmt.executequery (SQL);
while (Res.next ()) {//System.out.println (String.valueof (Res.getint (1)) + "\ T" + res.getstring (2)); }//The number of rows in the statistics//because the hive QL performs MapReduce, the issue to be aware of is the permissions issue//Because, at run time, temporary text is stored in the directory of/TMP in HDFS
        Pieces//Specific error: Permission denied:user=root, Access=execute, inode= "/tmp/hadoop-yarn": hadoop:supergroup:drwx------
Workaround: Modify the Execute permission of/TMP or run the program with user name consistency//sql = "SELECT COUNT (1) from" + TableName;
System.out.println ("Running:" + sql);
res = stmt.executequery (SQL);
 while (Res.next ()) {//System.out.println (res.getstring (1));//}}}