JDBC -----对结果集的系列操作

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JDBC --对结果集操作

一.读取结果集的方式；

a.从上往下进行读取，也就是往前操作

Class.forName("com.mysql.jdbc.Driver");      Connectionconn=DriverManager.getConnection("jdbc:mysql://localhost:3306/homework","root","");                String sql=" update tab set Chinese =Chinese+10 where id=1"; Statement stm=conn.createStatement(); String sql1=" select * from tab "; ResultSet rs=stm.executeQuery(sql1);  System.out.println("第一次读出数据"); System.out.println("id"+"\t"+"Chinese"+"\t"+"English"+"\t"+"Math");

                //从上往下进行操作 while(rs.next()) { System.out.println(rs.getInt("id")+"\t"+rs.getInt("Chinese")+"\t" +rs.getInt("English")+"\t" +rs.getInt("Math")); }

</pre><pre name="code" class="java">第2种<span style="font-family: Arial, Helvetica, sans-serif; background-color: rgb(255, 255, 255);">.： 从下往上进行读取，往后就是操作</span>

<span style="font-family: Arial, Helvetica, sans-serif; background-color: rgb(255, 255, 255);">条件是：</span>

<span style="font-family:Arial, Helvetica, sans-serif;"><span style="background-color: rgb(255, 255, 255);">          1.结果集的游标必须是在表中的最后一行。</span></span>

<span style="font-family:Arial, Helvetica, sans-serif;"><span style="background-color: rgb(255, 255, 255);"></span></span>

<span style="font-family:Arial, Helvetica, sans-serif;"><span style="background-color: rgb(255, 255, 255);">如：</span></span>

<span style="font-family:Arial, Helvetica, sans-serif;"><span style="background-color: rgb(255, 255, 255);">//从下往上读取</span></span>

<span style="font-family: Arial, Helvetica, sans-serif; background-color: rgb(255, 255, 255);"></span><pre name="code" class="java"> while(rs.previous()) { System.out.println(rs.getInt("id")+"\t"+rs.getInt("Chinese")+"\t" +rs.getInt("English")+"\t" +rs.getInt("Math")); }

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