JDBC练习_update语句和DDL语句
作者:互联网
JDBC练习_update语句
account表 修改记录:
/** * account表 修改记录 */ public class JDBCDemo03 { public static void main(String[] args) { Connection conn = null; Statement stmt = null; try { //1.注册驱动 Class.forName("com.mysql.cj.jdbc.Driver"); //2.获取连接对象 conn = DriverManager.getConnection("jdbc:mysql:///db1", "root", "root"); //3.定义sql String sql = "update account set balance = 1500 where id = 3"; //4.获取执行sql的对象 stmt = conn.createStatement(); //5.执行sql int count = stmt.executeUpdate(sql); //6.处理结果 System.out.println(count); if (count>0){ System.out.println("修改成功"); }else { System.out.println("修改失败"); } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException throwables) { throwables.printStackTrace(); }finally { //7.释放资源 if (stmt!=null){ try { stmt.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } if (conn!=null){ try { conn.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } } } }
JDBC练习_delete、DDL语句
删除account表中的记录:
/** * account表 删除一条记录 */ public class JDBCDemo04 { public static void main(String[] args) { Connection conn = null; Statement stmt = null; try { //1.注册驱动 Class.forName("com.mysql.cj.jdbc.Driver"); //2.获取连接对象 conn = DriverManager.getConnection("jdbc:mysql:///db1", "root", "root"); //3.定义sql String sql = "delete from account where id = 3"; //4.获取执行sql的对象 stmt = conn.createStatement(); //5.执行sql int count = stmt.executeUpdate(sql); //6.处理结果 System.out.println(count); if (count>0){ System.out.println("删除成功"); }else { System.out.println("删除失败"); } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException throwables) { throwables.printStackTrace(); }finally { //7.释放资源 if (stmt!=null){ try { stmt.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } if (conn!=null){ try { conn.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } } } }
执行DDL语句:
/** * 执行DDL语句 */ public class JDBCDemo05 { public static void main(String[] args) { Connection conn = null; Statement stmt = null; try { //1.注册驱动 Class.forName("com.mysql.cj.jdbc.Driver"); //2.获取连接对象 conn = DriverManager.getConnection("jdbc:mysql:///db1", "root", "root"); //3.定义sql String sql = "create table acc1(id int,name varchar(20))"; //4.获取执行sql的对象 stmt = conn.createStatement(); //5.执行sql int count = stmt.executeUpdate(sql); //6.处理结果 System.out.println(count); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException throwables) { throwables.printStackTrace(); }finally { //7.释放资源 if (stmt!=null){ try { stmt.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } if (conn!=null){ try { conn.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } } } }
标签:语句,JDBC,throwables,update,stmt,sql,catch,null,conn 来源: https://www.cnblogs.com/xjw12345/p/16521056.html