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JDBC读写mysql总结

Jun 07, 2016 pm 03:08 PM
jarjdbcmysqldownloadSummarizeRead and writedrive

一、下载驱动(主要是jar包) mysql-connection-java-5.1.31-bin.jar 二、添加jar包,配置环境变量 把驱动jar包添加到以下两个目录,并设置classpath环境变量。 1. 添加目录: (CATALINA_HOME) D:\..\Tomcat 6.0\lib\ (JAVA_HOME) D:\..\jdk1.7\jre\lib\ 2.

一、下载驱动(主要是jar包)

mysql-connection-java-5.1.31-bin.jar

 

二、添加jar包,配置环境变量

把驱动jar包添加到以下两个目录,并设置classpath环境变量。

 

1. 添加目录:

(CATALINA_HOME)     D:\..\Tomcat 6.0\lib\

(JAVA_HOME)         D:\..\jdk1.7\jre\lib\

                                                        

2. 添加环境变量:classpath

 -----记得添加jar包之后要设置环境变量!!!pythonMySQLdb其实也是一样的,都要环境变量设置

D:\mysql-connector-java-5.1.31\mysql-connector-java-5.1.31-bin.jar;

%JAVA_HOME%\jre\lib\mysql-connector-java-5.1.31-bin.jar;

%CATALINA_HOME%\lib\mysql-connector-java-5.1.31-bin.jar;

 

3.eclipse设置mysql驱动

在eclipse的“首选项”里,SQL Explorer里选择JDBC Driver,编辑右侧MySQL Driver。

Extra Class Path选项卡,Add按钮,添加驱动jar包mysql-connection-java-5.1.31-bin.jar,并设置DriverClass Name为com.mysql.jdbc.Driver。

 

4. 项目构建路径引入外部JAR为驱动jar包

(然后就可以写jdbc链接数据库程序了,程序见下,如果直接要写.sql脚本,还需要第5步)

 

5.sql脚本直接链接数据库

打开透视图SQL Explorer,在Connection视窗里,右键新建链接Create New Connection Profile,

Name乱写,如testyy;

Driver为MySQL Driver;

URL为jdbc:mysql://localhost:3306/testdb  -------(你自己的数据库名字为testdb)

User Name为root  ------这里千万为root!!!安装mysql的时候配置选择了"默认",用户永远都是root,只是改了密码而已

Password为mysql密码;

勾上Auto Logon,点击确定;

右键Connection链接,新建New SQL Editor,编辑.sql脚本:select * from table;

点击左上角“奔跑的人”按钮,下面有输出,跟在mysql命令行里一样。

-------------

单独的jdbcDemo.java程序:

package com.hadoop.mysql;

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

/**
 * @Note:链接数据库时需要"添加构建路径",添加jar包:为jdbc驱动----"mysql-connector-java-5.1.31-bin.jar"
 * 		注意数据库名字为testdb(写在url里),表名字为student(写在sql里的selete * from student里)
 *
 */
public class MyJdbcDemo {
	public static void main(String[] args) {
		String driver = "com.mysql.jdbc.Driver"; //驱动Driver
		String url = "jdbc:mysql://localhost:3306/testdb"; //url,数据库名字为testdb
		String user = "root"; //username------注意用户名一定是root!!! 用户名只能默认是root
		String password = "mysql"; //pwd-----密码可以为mysql,反正自己设置的
		
		try {
			Class.forName(driver); //加载驱动
			Connection conn = DriverManager.getConnection(url, user, password); //建立连接
			if(!conn.isClosed()){
				System.out.println("Succeed connecting to the database!");
			}
			Statement statement = conn.createStatement(); //执行SQL的statement
			String sql = "select * from student"; //sql语句,表名称为student
			ResultSet result = statement.executeQuery(sql); //结果集result
			System.out.println("执行结果:");
			System.out.println("sno"+"\t"+"sname"+"\t"+"sex"+"\t"+"bdate"+"\t"+"height");			
			while(result.next()){	
				System.out.print(result.getString("sno") + "\t");
				System.out.print(result.getString("sname") + "\t"); //选择sname这列数据
				System.out.print(result.getString("sex") + "\t");
				System.out.print(result.getString("bdate") + "\t");
				System.out.println(result.getString("height"));
			}
			result.close();
			conn.close();
			
		} catch (ClassNotFoundException e) {
			System.out.println("cannot find the driver!");
		} catch (SQLException e) {
			e.printStackTrace();
			System.out.println("SQLException!");
		}	
		
	}

}

在控制台里的结果:

JDBC读写mysql总结

在数据库表里看到的结果,(这里就不打开mysql终端看了,在SQL Explorer里也一样可以看到结果):

JDBC读写mysql总结


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