JDBC系列教材 （三）- 增、删、改

CRUD是最常见的数据库操作，即增删改查 
C 增加(Create) 
R 读取查询(Retrieve) 
U 更新(Update) 
D 删除(Delete) 

在JDBC中增加，删除，修改的操作都很类似，只是传递不同的SQL语句就行了。 

查询因为要返回数据，所以和上面的不一样，将在查询章节讲解。

步骤1:增加
步骤2:删除
步骤3:修改
步骤4:练习-增 删 改
步骤5:答案-增 删 改

步骤 1 : 增加

这段代码就是Hello JDBC中的代码，用于向数据库中插入数据

package jdbc;

   

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

import java.sql.Statement;

   

public class TestJDBC {

    public static void main(String[] args) {

   

        try {

            Class.forName("com.mysql.jdbc.Driver");

        } catch (ClassNotFoundException e) {

            e.printStackTrace();

        }

   

        try (

            Connection c = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/how2java?characterEncoding=UTF-8",

                "root", "admin");

            Statement s = c.createStatement();              

        )

        {

            String sql = "insert into hero values(null," + "'提莫'" + "," + 313.0f + "," + 50+ ")";

            s.execute(sql);

               

        } catch (SQLException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }

}

步骤 2 : 删除

删除和增加很类似，只不过是执行的SQL语句不一样罢了

package jdbc;

   

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

import java.sql.Statement;

   

public class TestJDBC {

    public static void main(String[] args) {

   

        try {

            Class.forName("com.mysql.jdbc.Driver");

        } catch (ClassNotFoundException e) {

            e.printStackTrace();

        }

   

        try (

            Connection c = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/how2java?characterEncoding=UTF-8",

                "root", "admin");

            Statement s = c.createStatement();              

        )

        {

            String sql = "delete from hero where id = 5";

            s.execute(sql);

               

        } catch (SQLException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }

}

步骤 3 : 修改

修改也一样，执行另一条SQL语句就可以了

package jdbc;

   

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

import java.sql.Statement;

   

public class TestJDBC {

    public static void main(String[] args) {

   

        try {

            Class.forName("com.mysql.jdbc.Driver");

        } catch (ClassNotFoundException e) {

            e.printStackTrace();

        }

   

        try (

            Connection c = DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/how2java?characterEncoding=UTF-8",

                "root", "admin");

            Statement s = c.createStatement();              

        )

        {

            String sql = "update hero set name = 'name 5' where id = 3";

            s.execute(sql);

               

        } catch (SQLException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }

}

更多内容，点击了解： https://how2j.cn/k/jdbc/jdbc-crud/705.html