Require
Login to database
Create table
Insert data
Java statement
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import com.mysql.cj.jdbc.Driver;
import java.util.Scanner;
public class JDBCDemo1 {
Connection connection;
public int id;
public String name;
public String tel;
public String sex;
//注册驱动 获取连接
public void DriverManager() throws SQLException {
//第一步:注册驱动 DriverManagere驱动
DriverManager.registerDriver(new Driver());
//第二步:获取连接
connection = DriverManager.getConnection
("jdbc:mysql://localhost:3306/school_java","root","1234"); //1234密码
//localhost：本地主机 3306：数据库端口号 school_java：具体数据库名字 root：用户名
}
//添加数据
public void add(int id, String name, String tel, String sex) throws SQLException {
//第三步:获取statement对象
PreparedStatement preparedStatement =
connection.prepareStatement("insert into student values(?,?,?,?);");
preparedStatement.setInt(1, id);
preparedStatement.setString(2, name);
preparedStatement.setString(3, tel);
preparedStatement.setString(4, sex);
//第四步: 执行SQL语句返回结果集
preparedStatement.executeUpdate();//executeUpdate只要修改数据就用，不管是增删改
}
//获取couse表中的所有数据
public void Statement() throws SQLException {
//第三步:获取statement对象
PreparedStatement preparedStatement =
connection.prepareStatement("select * from student;");//MySQL语句
//第四步: 执行SQL语句返回结果集
ResultSet resultset = preparedStatement.executeQuery();//executeQuery只有查询用
//集合存储
//第五步:遍历结果集
while(resultset.next()) {
//next：判断是否有下一条数据
System.out.print(resultset.getInt("id") + " ");
//数据库里什么字段，get方法就填什么类型
System.out.println(resultset.getString("name")+ " " + resultset.getString("tel")
+ " " + resultset.getString("sex"));
}
//第六步:关闭连接释放资源
resultset.close();
preparedStatement.close();
}
//关闭连接
public void close() throws SQLException {
connection.close();
}
//删除数据
private void delete(int id) throws SQLException {
PreparedStatement preparedStatement =
connection.prepareStatement("delete from student where id = ?");
preparedStatement.setInt(1, id);
//执行Sql语句
preparedStatement.executeUpdate();
}
//修改名字数据方法
private void Name(int id, String name) throws SQLException {
PreparedStatement preparedStatement =
connection.prepareStatement("update student set name = ? where id = ?;");
preparedStatement.setString(1, name);
preparedStatement.setInt(2, id);
//执行Sql语句
preparedStatement.executeUpdate();
}
//查询电话
public void Tel(String tel) throws SQLException {
//第三步:获取statement对象
PreparedStatement preparedStatement =
connection.prepareStatement("select * from student where tel like ?;");//不能写入通配符
preparedStatement.setString(1, tel);
//第四步: 执行SQL语句返回结果集
ResultSet resultset = preparedStatement.executeQuery();
while(resultset.next()) {
//next：判断是否有下一条数据
System.out.print(resultset.getInt("id") + " ");
//数据库里什么字段，get方法就填什么类型
System.out.println(resultset.getString("name")+ " " + resultset.getString("tel")
+ " " + resultset.getString("sex"));
}
}
//修改电话数据方法
private void Tel1(int id, String tel) throws SQLException {
PreparedStatement preparedStatement =
connection.prepareStatement("update student set tel = ? where id = ?;");
preparedStatement.setString(1, tel);
preparedStatement.setInt(2, id);
//执行Sql语句
preparedStatement.executeUpdate();
}
//查询性别
public void Sex(String sex) throws SQLException {
//第三步:获取statement对象
PreparedStatement preparedStatement =
connection.prepareStatement("select * from student where sex = ? ");//MySQL语句
preparedStatement.setString(1,sex);
//第四步: 执行SQL语句返回结果集
ResultSet resultset = preparedStatement.executeQuery();
while(resultset.next()) {
//next：判断是否有下一条数据
System.out.print(resultset.getInt("id") + " ");
//数据库里什么字段，get方法就填什么类型
System.out.println(resultset.getString("name")+ " " + resultset.getString("tel")
+ " " + resultset.getString("sex"));
}
}
public static void main(String[] args) throws SQLException {
// TODO Auto-generated method stub
JDBCDemo1 s = new JDBCDemo1();
Scanner in = new Scanner(System.in);
//连接数据库
s.DriverManager();
System.out.println("查询所有人信息：");
s.Statement();
// System.out.println("向表中新增三条数据：");
// s.add(11, "王总","16688775522", "男");
// s.add(12, "芳芳","15184057973", "女");
// s.add(13, "黄总","18199058864", "男");
// s.Statement();
System.out.println("查询表中电话以137开头的数据：");
s.Tel(in.next());
// System.out.println("修改第5条数据，电话改为“13124235300");
// s.Tel1(5, "13124235300");
// s.Statement();
System.out.println("查询性别为男的数据：");
s.Sex(in.next());
// System.out.println("修改id为10的名字改为大帅哥：");
// s.Name(10, "大帅哥");
// s.Statement();
System.out.println("查询表中电话以131开头的数据：");
s.Tel(in.next());
// System.out.println("删除表中第3条数据：");
// s.delete(3);
// s.Statement();
System.out.println("查询性别为女的数据：");
s.Sex(in.next());
System.out.println("查询所有人信息：");
s.Statement();
s.close();
}
}