7.JDBC增删改查操作

①首先加载驱动,创建连接,申明Statement.
②申明sql语句,用excuteUpdate方法运行.
这节课基本不用复习,只有一个prepareStatement和setString新方法.这种方法更加具有可读性.

package javastudy;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.ResultSetMetaData;import java.sql.SQLException;import java.sql.Statement;public class Test1 {    public static void main(String[] args) throws ClassNotFoundException, SQLException    {        Class.forName("com.mysql.jdbc.Driver");        Connection conn=DriverManager.getConnection("jdbc:mysql://localhost/student?&useSSL=true", "jake", "123456");        Statement st=conn.createStatement();        //*************2.更改数据******************        //2.1增加数据        //String sql="insert into studinfo values('004','赵六','男',18)";        //2.2修改数据        //String sql="update studinfo set name='张三' where name='zhangsan'";        //2.3删除数据        //String sql="delete from studinfo where no ='004'";//      String sql="delete from studinfo where no ='004'";//      st.executeUpdate(sql);        //st.executeUpdate("update studinfo set name='zhangsan' where name='张三'");        //*************3.******************        String sql="insert into studinfo values(?,?,?,?)";        PreparedStatement ps=conn.prepareStatement(sql);        ps.setString(1, "005");        ps.setString(2, "jack");        ps.setString(3, "男");        ps.setInt(4, 20);        ps.executeUpdate();        //*************1.获取列名称******************        ResultSet rs=st.executeQuery("select * from studinfo");        ResultSetMetaData data=rs.getMetaData();        for(int i=1;i<=data.getColumnCount();i++)        {            System.out.print(data.getColumnName(i)+"\t");        }        System.out.println();        while(rs.next())        {            for(int i=1;i<=4;i++)            {                System.out.print(rs.getString(i)+"\t");            }            System.out.println();        }    }}