Java使用mysql数据库实现增删改查

我在博客里有一篇《Java使用jdbc连接数据库》，连接成功以后就需要对数据库进行操作，今天这篇博文主要介绍我在Java中经常用到的数据库操作，只挑最常用的代码示例。

一.查找

public String getC_name(int c_id) {
        // TODO Auto-generated method stub
        String c_name="";
        Connection conn = DBUtil.getConnectDb();
        String sql="select * from customer where c_id=?";
        try {
            PreparedStatement stm = conn.prepareStatement(sql);
            stm.setInt(1, c_id);
            ResultSet rs = stm.executeQuery();
            if(rs.next())
            {
                c_name = rs.getString("c_name");
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return c_name;
    }

二.修改

public void is_loginInfo(int m_id,int is_login)
    {
        Connection conn = DBUtil.getConnectDb();
        String sql="update manager set is_login=? where m_id=?";
        PreparedStatement stm = null;
        try {
            stm = (PreparedStatement) conn.prepareStatement(sql);

            is_login=(is_login==1?0:1);
//            System.out.println(is_login);
            stm.setInt(1, is_login);
            stm.setInt(2, m_id); 
            stm.executeUpdate();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

三.插入

public int insertProduct(ProductBean item) {
        // TODO Auto-generated method stub
        Connection conn = DBUtil.getConnectDb();
        String sql="insert into product(p_name,p_money,p_totalnum,p_desc,back_money,p_id) values(?,?,?,?,?,?)";
        int rs = 0;
        try {
            PreparedStatement stm = conn.prepareStatement(sql);
            stm.setString(1, item.getP_name());
            stm.setInt(2, item.getP_money());
            stm.setInt(3, item.getP_totalnum());
            stm.setString(4, item.getP_desc());
            stm.setInt(5, item.getBack_money());
            stm.setInt(6, item.getP_id());
            rs = stm.executeUpdate();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return rs;
    }

四.删除

public static void main(String[] args)
    {
        Connection conn = DBUutil.getConnectDb();
        String sql="delete from user where name='scs'";
        PreparedStatement stm = null;
        ResultSet rs = null;
        int rss=0;
        try {

            stm = conn.prepareStatement(sql);
            rss=stm.executeUpdate(sql);
            System.out.println(rss);

        } catch (SQLException e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        finally
        {
            DBUutil.CloseDB(rs,stm,conn);
        }
    }