MySQL安裝與idea的連接實現

--編輯my.ini配置文件內容（Mysql 8.0以上不需要，直接安裝即可）
[mysql]
# 設置mysql客戶端默認字符集
default-character-set=utf8 
[mysqld]
#設置3306端口
port = 3306 
# 設置mysql的安裝目錄
basedir=E:\MySQL5.7.13\mysql-5.7.13-winx64
# 設置mysql數據庫的數據的存放目錄
datadir=E:\MySQL5.7.13\mysql-5.7.13-winx64\data
# 允許最大連接數
max_connections=200
# 服務端使用的字符集默認為8比特編碼的latin1字符集
character-set-server=utf8
# 創建新表時將使用的默認存儲引擎
default-storage-engine=INNODB
# 安裝好後, 免密碼進入mysql
skip-grant-tables

--用管理員身份運行cmd，輸入命令
//安裝mysql
mysqld -install 
//安裝成功後,初始化數據文件
mysqld --initialize-insecure --user=mysql
//進入mysql管理界面
mysql -u root-p
//修改密碼
update mysql.user set password=password('新密碼') where user='root';
//mysql8修改密碼
alter user 'root'@'localhost' identified by '密碼'

package jdbc_excise;

import java.sql.*;

public class Jdbc {
    public static void main(String[] args) throws SQLException {
        try {
            Class.forName("com.mysql.jdbc.Driver");

            String url = "jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=utf8&useSSL=false";
            //通用模板：jdbc：數據庫名字：//地址：端口/實際使用數據庫名稱?附加參數
            String username = "root";
            String password = "123456";

           Connection connection = DriverManager.getConnection(url,username,password);
           Statement statement = connection.createStatement();
            //執行sql查詢語句
           String sql = "select * from student";
           ResultSet resultSet = statement.executeQuery(sql);

           while (resultSet.next()){
               System.out.println("Sno="+resultSet.getObject("Sno"));
          }

           resultSet.close();
           statement.close();
           connection.close();

        } catch (ClassNotFoundException e) {
            e.printStackTrace();

        }
    }


}

--新建配置文件：db.properties--

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=utf8&useSSL=false
username=root
password=123456

package connect_jdbc.utils;

import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
import java.util.Properties;

public class JdbcUtils {
    private  static String driver = null;;
    private static String url =null;
    private static String username = null;
    private static  String password = null;

    static {
        try{
            //通過反射得到配置文件中的內容
           InputStream in = JdbcUtils.class.getClassLoader().getResourceAsStream("db.properties");
            Properties properties=new Properties();
            properties.load(in);

            driver = properties.getProperty("driver");
            url = properties.getProperty("url");
            username = properties.getProperty("username");
            password = properties.getProperty("password");

            //加載一次驅動
             Class.forName(driver);

        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }

    }
    //獲取連接
    public static Connection getConnection() throws SQLException {
        return DriverManager.getConnection(url,username,password);
    }
    //釋放連接
    public static  void release(Connection conn, Statement st, ResultSet rs){
        if(rs!=null){
            try {
                rs.close();
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
        }
        if(st!=null){
            try {
                st.close();
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
        }
        if(conn!=null){
            try {
                conn.close();
            } catch (SQLException throwables) {
                throwables.printStackTrace();
            }
        }
    }

}

//執行executeUpdate語句，實現增刪改
package connect_jdbc.utils;

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

public class JdbcTest {
    public static void main(String[] args) throws SQLException {
        Connection connection =null;
        Statement st = null;
        ResultSet rs =null;

        try {
            connection = JdbcUtils.getConnection();
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        st = connection.createStatement();
        String sql = "insert  into  student (sno, sname, ssex, sclass, stel, sgroup, spassword)" +
                "values (1907040136,'賀子奇','男','1900144','15735116626',3,'123456')";
        int i = st.executeUpdate(sql);//返回值為整型，表示有幾行受影響
        if(i>0){
            System.out.println("插入成功！");
        }
        JdbcUtils.release(connection,st,rs);
    }
}

//執行executeQuery語句，實現查找
package connect_jdbc.utils;

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

public class JdbcSelect {
    public static void main(String[] args) {
        Connection connection = null;
        Statement st = null;
        ResultSet res = null;
        try {
            connection = JdbcUtils.getConnection();
            st = connection.createStatement();
            String sqls = "select * from student";
            res = st.executeQuery(sqls);//返回值為查找的結果集
            while (res.next())//進行結果集的輸出
            {
                System.out.println(res.getObject("sno")+" "+res.getObject("sname"));
            }
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }

        JdbcUtils.release(connection,st,res);
    }
}

package connect_jdbc.utils;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class JdbcTestSe {
    public static void main(String[] args) {
        Connection connection =null;
        PreparedStatement statement = null;
        ResultSet res = null;
        try {
            connection = JdbcUtils.getConnection();
            //與statement的區別，要使用？占位符代替參數，進行一次預編譯
            String sql = "insert  into  student (sno, sname, ssex, sclass, stel, sgroup, spassword)" +
                    "values (?,?,?,?,?,?,?)";
            //手動給每一個參數（？）賦值
            statement=connection.prepareStatement(sql);
            statement.setString(1,"1907040124");
            statement.setString(2,"薛曉軍");
            statement.setString(3,"男");
            statement.setString(4,"19070144");
            statement.setString(5,"15735116626");
            statement.setString(6,"3");
            statement.setString(7,"123456");
			//執行
            int i = statement.executeUpdate();
            if(i>0)
            {
                System.out.println("插入成功！");
            }

        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }

        JdbcUtils.release(connection,statement,res);
    }
}