JDBC使用sql语句

JDBC---连接数据库

java与数据库连接需要驱动，这个驱动则是JDBC，连接的时候需要ip+端口号+dbname 还要用户名和密码

改java文件的编码方式--在项目名点右键属性----把编码方式改成UTF-8

改变页面jsp的编码方式--在MyEclipse点右键--preferences中改

点项目名右键属性：

建立4个包

必须要写这个方法：、

声明执行

当增、改、删的时候跟上面的程序差不多

可是当查的时候只能

package com.softteem.dbweb.db;

import java.sql.DriverManager;

import java.sql.Connection;

import java.sql.ResultSet;

public class ConnDB {

public static void getConn(){

		try {

			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

			String url="jdbc:sqlserver://128.0.38.13:1433;databaseName=three";

			String user="sa";

			String password="sasa";

			Connection conn=DriverManager.getConnection(url, user, password);

			String sql="insert into teacher values('李老师',35,1)";

			conn.createStatement().execute(sql);

			conn.close();

		} catch (Exception e) {

			// TODO Auto-generated catch block

			e.printStackTrace();

		}

	}

	public static void findAll(){

		try {

			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

			String url="jdbc:sqlserver://128.0.38.13:1433;databaseName=three";

			String user="sa";

			String password="sasa";

			Connection conn=DriverManager.getConnection(url, user, password);

			String sql="select * from teacher";

			ResultSet rs=conn.createStatement().executeQuery(sql);

			while(rs.next()){

				int tno=rs.getInt("tno");

				String tname=rs.getString("tname");

				int sex=rs.getInt("sex");

				int age=rs.getInt("age");

				System.out.println("tno="+tno+",tname="+tname+",sex="+sex+",age="+age);

			}

			conn.close();

		} catch (Exception e) {

			// TODO Auto-generated catch block

			e.printStackTrace();

		}

	}

	public static void main(String[] args) {

		findAll();

	}

}

把相同代码合在一起

更简便的方法：

作业

package com.softteem.dbweb.bean;

public class Teacher {

private int tno;

private String tname;

private int sex;

private int age;

public int getTno() {

	return tno;

}

public void setTno(int tno) {

	this.tno = tno;

}

public String getTname() {

	return tname;

}

public void setTname(String tname) {

	this.tname = tname;

}

public int getSex() {

	return sex;

}

public void setSex(int sex) {

	this.sex = sex;

}

public int getAge() {

	return age;

}

public void setAge(int age) {

	this.age = age;

}

}

package com.softteem.dbweb.dao;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

import com.softteem.dbweb.bean.Teacher;

import com.softteem.dbweb.db.ConnDB;

public class TeacherDao {

public static void insertOrUpdate(String sql){

	try {

		Connection conn=ConnDB.getConn();

		conn.createStatement().execute(sql);

		ConnDB.closeConn(conn);

	} catch (SQLException e) {

		// TODO Auto-generated catch block

		e.printStackTrace();

	}

}

public static List<Teacher> findAll(String sql){

	List<Teacher> list=new ArrayList<Teacher>();

	try {

		Connection conn=ConnDB.getConn();

		ResultSet rs=conn.createStatement().executeQuery(sql);

		while(rs.next()){

			int tno=rs.getInt("tno");

			String tname=rs.getString("tname");

			int sex=rs.getInt("sex");

			int age=rs.getInt("age");

			Teacher bean=new Teacher();

			bean.setTno(tno);

			bean.setTname(tname);

			bean.setSex(sex);

			bean.setAge(age);

			list.add(bean);

		}

		ConnDB.closeConn(conn);

	} catch (Exception e) {

		// TODO Auto-generated catch block

		e.printStackTrace();

	}

	return list;

}

public static void main(String[] args) {

	List<Teacher> list=findAll("select * from teacher");

	for (Teacher t : list) {

		System.out.println("编号："+t.getTno()+"姓名："+t.getTname()+"年龄："+t.getAge()+"性别："+t.getSex());

	}

}

}

package com.softteem.dbweb.db;

import java.sql.DriverManager;

import java.sql.Connection;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.List;

public class ConnDB {

public static Connection getConn(){

Connection conn=null;

try {

Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

String url="jdbc:sqlserver://128.0.38.13:1433;databaseName=three";

String user="sa";

String password="sasa";

conn=DriverManager.getConnection(url, user, password);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return conn;

}

public static void closeConn(Connection conn){

if(conn!=null){

try {

conn.close();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

}

巴特西

JDBC使用sql语句

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