(1)复习jdbc操作,编译mybatis源码,准备为你的简历加分吧

qq123 2021年02月13日编程语言 475 0

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1.mybatis的底层是jdbc操作,我们来回顾一下,如下

public static void main(String[] args)  { 
    String url="jdbc:mysql://10.3.11.64:3306/pdzx?characterEncoding=utf8&useSSL=false&allowMultiQueries=true"; 
    String user="pdzx_pro"; 
    String password="cde35TGB3910"; 
 
    String sql = "  SELECT t2.id AS sectionId , t2.proj_id AS projId , t2.section_name AS sectionName " + 
      "FROM b_proj_base_info AS t1 JOIN b_proj_section_info AS t2 ON t1.id=t2.proj_id " + 
      "WHERE t2.proj_id=? AND t2.section_name LIKE CONCAT('%',?,'%')"; 
    //连接数据库 
    try { 
      Class.forName("com.mysql.cj.jdbc.Driver"); 
      //建立连接 
      Connection conn = DriverManager.getConnection(url, user, password); 
      //得到ResultSet结果集 
      PreparedStatement preparedStatement = conn.prepareStatement(sql); 
      preparedStatement.setString(1, "0124569b738e405fb20b68bfef37f487");    //为第一个问号赋值 
      preparedStatement.setString(2, "标段");    //为第二个问号赋值 
      ResultSet resultSet = preparedStatement.executeQuery(); 
      //遍历结果集 
      while (resultSet.next()) { 
        int sectionId = resultSet.getInt("sectionId"); 
        String projId = resultSet.getString("projId"); 
        String sectionName = resultSet.getString("sectionName"); 
        System.out.println(sectionId+"----->"+projId+"----->"+sectionName); 
      } 
      resultSet.close(); 
      //释放资源 
      preparedStatement.close(); 
      conn.close(); 
    } catch (Exception e) { 
      e.printStackTrace(); 
    } 
  }