Hive的JDBC使用&并把JDBC放置后台运行

使用JDBC访问HIVE:

首先启动hive的JDBC服务.

进入hive的bin目录:

这样启动是启动到前台.如果要想启动到后台需要用到Linux的相关命令.

我们先把其放到前台看下效果,之后再把它放到后台.

查看这个启动的服务是否已经能够监听到了.

这之后就可以编写JDBC代码了.

以word count为例子.

示例代码如下:

 1 import java.sql.Connection;
 2 import java.sql.DriverManager;
 3 import java.sql.PreparedStatement;
 4 import java.sql.ResultSet;
 5 
 6 public class HiveJdbc {
 7     private static String driverName = "org.apache.hive.jdbc.HiveDriver";
 8     private static String url = "jdbc:hive2://192.168.1.99:10002/default";
 9     private static String user = "root";
10     private static String password = "";
11     private static String sql = "";
12     private static ResultSet res;
13     
14     public static void main(String[] args) throws Exception {
15         Class.forName(driverName);
16         Connection conn = DriverManager.getConnection(url, user, password);
17         sql = "select word,count(word) as count from (select explode(split(line,' ')) word from t_wordcount) w group by word";
18         PreparedStatement prepStmt = conn.prepareStatement(sql);
19         res = prepStmt.executeQuery();
20         while(res.next()){
21             String word = res.getString(1);
22             int count = res.getInt(2);
23             System.out.println(word + ", " +count);
24         }
25         res.close();
26         prepStmt.close();
27         conn.close();
28     }
29 }

运行...

没有报任何错误.

然后前面设置端口,在前台的运行的标签页中运行MR....

要把这个放在服务任务放在后台执行:

要用到Linux中的nohup