在PHP中将多个SQL查询写入一个CSV

Question

我现在有一个成功运行的php脚本，它将sql查询的结果写入CSV文件，最终作为附件邮寄。到目前为止一切都那么好，但是我需要添加另一个类似的查询，基本上只进行一些求和，但是，我希望它在第一个之后运行并让它们都写入CSV。

希望/理想情况下，编写查询1的结果，跳过几个空白行，并写出查询2的结果。如果我可以为第二个查询添加一个标题，说“CSR Totals”但我是我不甘心。

无论如何，我不确定该怎么做。我会想象使用mysqli_multiple_queries？我不想因为它运作良好而重构太多我所拥有的东西，但我意识到我必须改变一些事情。这不是我的专业领域，所以我希望得到一些指导性的建议。

这是代码:(注意我已经连接了第二个查询，但只是为了显示我的概念，我不确定语法是否正确。）

    $result = mysqli_query($conn2,
        "SELECT  
          firstn
          , lastn
        , extension
        , Recieved
        , RecievedKnown
        , Outbound
        , outboundKnown

            FROM (
          SELECT 
             firstn
           , lastn   
           , c.extension
           ,CASE WHEN LEGTYPE1 = 2 AND ANSWERED = 1 THEN 'x' ELSE '' END AS Recieved
           , case when LEGTYPE1 = 2 and answered = 1 and CALLINGPARTYNO = k.phone_number then 'x' ELSE '' end as RecievedKnown
           , CASE WHEN ANSWERED = 1 AND LEGTYPE1 = 1 then 'x' ELSE '' end  AS Outbound
           , case when LEGTYPE1 = 1 and FINALLYCALLEDPARTYNO = k.phone_number then 'x' ELSE '' end as outboundKnown

          FROM test.session a
          INNER JOIN test.callsummary b ON a.NOTABLECALLID = b.NOTABLECALLID
          right join jackson_id.users c on a.callingpartyno = c.extension or a.finallycalledpartyno = c.extension
          LEFT JOIN test.known_numbers k ON a.callingpartyno = k.phone_number
          WHERE a.ts >= curdate()
          and(a.CALLINGPARTYNO in (select extension from test.test_users) OR a.finallycalledpartyno IN (select extension from test.test_users))

         ) x
         ORDER BY extension;") or die(mysqli_error( $conn2));




         $result .= mysqli_query($conn2,
            "//2nd query in here") or die(mysqli_error( $conn2));




          if (!$result) die('Couldn\'t fetch records');
          $num_fields = mysqli_num_fields($result);
          $headers = array();
          while ($fieldinfo = mysqli_fetch_field($result)) {
              $headers[] = $fieldinfo->name;
          }
          $fp = fopen('test.csv', 'w');
          if ($fp && $result) {
              fputcsv($fp, $headers);
              while ($row = $result->fetch_array(MYSQLI_NUM)) {
                  fputcsv($fp, array_values($row));
              }
                fclose($fp);
          }


          $file = "test.csv";