JDBC练习_update语句与JDBC练习_update、DDL语句

JDBC练习_update语句　

需求:修改account表中的数据:

package CN.XueQiang.JDBC;

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

/**
 * 修改accont表中的数据
 */
public class JDBCDemo3 {
    public static void main(String[] args) {
        Statement statement = null;
        Connection conn = null;
        try {
            //1.注册驱动
            Class.forName("com.mysql.jdbc.Driver");
            //2.获取数据库创建连接对象
             conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/win", "root", "njzyb555");
            //3.定义sql
            String sql = "update accont set balance =1500 where id=1;";
            //4.获取执行sql对象
            statement = conn.createStatement();
            //5.执行sql
            int i = statement.executeUpdate(sql);
            System.out.println(i);
            if (i > 0) {
                System.out.println("修改成功");
            } else {
                System.out.println("修改失败");
            }
        } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            //7.释放资源
            if (statement != null) ;
            try {
                statement.close();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            if (conn !=null){
                try {
                    conn.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }
        }

    }
}

修改结果

 

修改之后的accont

 

 JDBC练习_update、DDL语句

需求:删除account表中的数据:

package CN.XueQiang.JDBC;

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

/**
 *删除accont表中的数据;
 */
public class JDBCDem04 {
    public static void main(String[] args) {
        Connection conn = null;
        Statement stat = null;
        try {
            //1.注册驱动
            Class.forName("com.mysql.jdbc.Driver");
            //2.获取数据库创建连接对象
            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/win", "root", "njzyb555");
            //3.定义sql
            String sql = "delete from accont where  id = 3";
            //4.获取执行sql对象
            stat = conn.createStatement();
            //5.执行sql
            int i = stat.executeUpdate(sql);
            System.out.println(i);
            if (i>0){
                System.out.println("删除成功!");
            }else{
                System.out.println("删除失败");
            }
        } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }finally {
            //7.释放资源
            if (stat !=null) {
                try {
                    stat.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
                if (conn !=null) {
                    try {
                        conn.close();
                    } catch (SQLException e) {
                        throw new RuntimeException(e);
                    }
                }
            }
        }
    }
}

 

 删除前

 

 删除后