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我一直在为以下代码苦苦挣扎。我是 PHP 新手。这段 mysql 代码 100% 在 phpmyadmin 中工作。我正在使用<?php echo $row['Rank'];?>，但我只为所有学生获得 1 个。但是sql代码工作正常。我在这里制作了 sql fiddle http://sqlfiddle.com/#!2/24855/1请帮帮我。

Select Distinct regd, Roll_no, Name_of_Student, Test_date,
English, f_eng, Mizo, f_mz,  Hindi, f_hn,  Mathematics,  f_maths, SS, f_ss, Science, 
f_sc, score, fmscore, perc, Rank FROM (SELECT *, IF(@marks = (@marks := score), @auto, 
@auto := @auto + 1) AS Rank FROM
(SELECT regd, Roll_no, Name_of_Student, Test_date,
SUM( IF( `Subject` = 'English', Mark_score, 0 ) ) AS English,
SUM( IF( `Subject` = 'English', Full_mark, 0 ) ) AS f_eng, 
SUM( IF( `Subject` = 'Mizo', Mark_score, 0 ) ) AS Mizo,
SUM( IF( `Subject` = 'Mizo', Full_mark, 0 ) ) AS f_mz, 
SUM( IF( `Subject` = 'Hindi', Mark_score, 0 ) ) AS Hindi,
SUM( IF( `Subject` = 'Hindi', Full_mark, 0 ) ) AS f_hn, 
SUM( IF( `Subject` = 'Mathematics', Mark_score, 0 ) ) AS Mathematics, 
SUM( IF( `Subject` = 'Mathematics', Full_mark, 0 ) ) AS f_maths, 
SUM( IF( `Subject` = 'SS', Mark_score, 0 ) ) AS SS,
SUM( IF( `Subject` = 'SS', Full_mark, 0 ) ) AS f_ss, 
SUM( IF( `Subject` = 'Science', Mark_score, 0 ) ) AS Science,
SUM( IF( `Subject` = 'Science', Full_mark, 0 ) ) AS f_sc,
SUM(Full_mark) AS fmscore,
SUM(Mark_score) AS score, SUM(Mark_score)/SUM(Full_mark)*100 as perc FROM cxexam,
(SELECT @auto := 0, @marks := 0) AS init GROUP BY regd ORDER BY score DESC) t) AS result where Test_date between '2013-07-01' and '2013-07-31'

这是PHP部分。好像没问题。它还正确地回显所有内容，只是它没有正确输出排名。在排名行中，它仅显示 1为所有学生的排名。您可以从下面的代码中了解我想要实现的目标。我真的需要你的帮助。我知道你们很熟悉这样的问题。

<table width="800" border="1" class="tablestyle" cellpadding="8" cellspacing="6">
<tr> 
    <th align="center" width="80">Roll No</th>
    <th align="center" width="100">Name_of_Student</th>
    <th align="center" width="40">English</th>
    <th align="center" width="55">Mizo</th>
    <th align="center" width="55">Hindi</th>
    <th align="center" width="55">Math</th>
    <th align="center" width="70">SS</th>
    <th align="center" width="40">Science</th>
     <th align="center" width="70">FM</th>
      <th align="center" width="70">MO</th>
      <th align="center" width="40">Percentage</th>
      <th align="center" width="40">Rank</th>
      <th align="center" width="40">Result</th>

</tr>
<?php 
    while($row=mysql_fetch_array($res))
    {
?>
<tr>
    <td align="center"><?php echo $row['Roll_no'];?></td>
    <td align="left"><?php echo $row['Name_of_Student'];?></td>
    <td align="center"><?php echo $row['English'];?></td>
    <td align="center"><?php echo $row['Mizo'];?></td>
    <td align="center"><?php echo $row['Hindi'];?></td>
    <td align="center"><?php echo $row['Mathematics'];?></td>
    <td align="center"><?php echo $row['SS'];?></td>
    <td align="center"><?php echo $row['Science'];?></td>
    <td align="center"><?php echo $row['fmscore'];?></td>
    <td align="center"><?php echo $row['score'];?></td>
    <td align="center"><?php echo number_format($row['perc'],0);?>%</td>
    <td><?php echo $row['Rank']; ?></td>
    <td><?php 
    if ($row['English']/$row['f_eng']*100>=40 && $row['Mizo']/$row['f_mz']*100>=40 && $row['Hindi']/$row['f_hn']*100>=40 && $row['Mathematics']/$row['f_math']*100>=40 && $row['SS']/$row['f_ss']*100>=40 && $row['Science']/$row['f_sc']*100>=40)
   {
   echo "<font color=green>Passed</font>";
   }
   else 
   {
   echo "<font color=red>Failed</font>";
   }
   ?></td>

</tr>
<?php
    }
?>
</table>

不工作的部分：rank和result。任何帮助表示赞赏。

4

3 回答 3

2

您的 sql 代码存在几个问题（例如，从不混合DISTINCTand GROUP BY，WHERE在内部选择中使用等）。话虽如此，您的查询应该类似于

SELECT regd, Roll_no, Name_of_Student, Test_date,
       English, f_eng, 
       Mizo, f_mz,  
       Hindi, f_hn,  
       Mathematics,  f_maths, 
       SS, f_ss, 
       Science, f_sc, 
       score, fmscore, perc, Rank 
FROM 
(
  SELECT t.*, IF(@p = score, @n, @n := @n + 1) AS Rank, @p := score 
    FROM
  (
    SELECT regd, Roll_no, Name_of_Student, Test_date,
            SUM(IF(Subject = 'English'    , Mark_score, 0)) English,
            SUM(IF(Subject = 'English'    , Full_mark,  0)) f_eng, 
            SUM(IF(Subject = 'Mizo'       , Mark_score, 0)) Mizo,
            SUM(IF(Subject = 'Mizo'       , Full_mark,  0)) f_mz, 
            SUM(IF(Subject = 'Hindi'      , Mark_score, 0)) Hindi,
            SUM(IF(Subject = 'Hindi'      , Full_mark,  0)) f_hn, 
            SUM(IF(Subject = 'Mathematics', Mark_score, 0)) Mathematics, 
            SUM(IF(Subject = 'Mathematics', Full_mark,  0)) f_maths, 
            SUM(IF(Subject = 'SS'         , Mark_score, 0)) SS,
            SUM(IF(Subject = 'SS'         , Full_mark,  0)) f_ss, 
            SUM(IF(Subject = 'Science'    , Mark_score, 0)) Science,
            SUM(IF(Subject = 'Science'    , Full_mark,  0)) f_sc,
            SUM(Full_mark) fmscore,
            SUM(Mark_score) score, 
            SUM(Mark_score) / SUM(Full_mark) * 100 perc 
      FROM cxexam, (SELECT @n := 0, @p := 0) n 
     WHERE Test_date BETWEEN '2013-07-01' AND '2013-07-31'
     GROUP BY regd 
     ORDER BY score DESC
  ) t
) r

这是SQLFiddle演示

现在php代码

$link = mysql_connect('localhost', 'user', 'password');
if (!$link) {
    die('Could not connect: ' . mysql_error());
}
$db_selected = mysql_select_db('dbname', $link);
if (!$db_selected) {
    die ('Can\'t use db : ' . mysql_error());
}

$sql = "
    SELECT regd, Roll_no, Name_of_Student, Test_date,
           English, f_eng, 
           Mizo, f_mz,  
           Hindi, f_hn,  
           Mathematics,  f_maths, 
           SS, f_ss, 
           Science, f_sc, 
           score, fmscore, perc, Rank 
    FROM 
    (
      SELECT t.*, IF(@p = score, @n, @n := @n + 1) AS Rank, @p := score 
        FROM
      (
        SELECT regd, Roll_no, Name_of_Student, Test_date,
                SUM(IF(Subject = 'English'    , Mark_score, 0)) English,
                SUM(IF(Subject = 'English'    , Full_mark,  0)) f_eng, 
                SUM(IF(Subject = 'Mizo'       , Mark_score, 0)) Mizo,
                SUM(IF(Subject = 'Mizo'       , Full_mark,  0)) f_mz, 
                SUM(IF(Subject = 'Hindi'      , Mark_score, 0)) Hindi,
                SUM(IF(Subject = 'Hindi'      , Full_mark,  0)) f_hn, 
                SUM(IF(Subject = 'Mathematics', Mark_score, 0)) Mathematics, 
                SUM(IF(Subject = 'Mathematics', Full_mark,  0)) f_maths, 
                SUM(IF(Subject = 'SS'         , Mark_score, 0)) SS,
                SUM(IF(Subject = 'SS'         , Full_mark,  0)) f_ss, 
                SUM(IF(Subject = 'Science'    , Mark_score, 0)) Science,
                SUM(IF(Subject = 'Science'    , Full_mark,  0)) f_sc,
                SUM(Full_mark) fmscore,
                SUM(Mark_score) score, 
                SUM(Mark_score) / SUM(Full_mark) * 100 perc 
          FROM cxexam, (SELECT @n := 0, @p := 0) n 
         WHERE Test_date BETWEEN '2013-07-01' AND '2013-07-31'
         GROUP BY regd 
         ORDER BY score DESC
      ) t
    ) r";

$result = mysql_query($sql);
if(!$result) {
    die(mysql_error()); // TODO: better error handling
}

while($row = mysql_fetch_assoc($result)) {
    echo "{$row['regd']} - {$row['Rank']}<br>";
}

输出（如预期）：

40 - 1
2 - 2
3 - 2
20 - 3
于 2013-07-21T06:52:02.823 回答
1

对于排名部分，这是 100% 的工作。看来你不是很了解php。

<?php 
$rank = $prevScore = 0; 
{     
$count++; // always increment
if ($row_dep['perc'] > $prevScore) {
//whenever a non-tie occurs the my rank catches up
$my_rank = $count;
$rank = $count;
} else {
//whenever a tie occurs, just use the my rank
$rank = $my_rank;
}  
$prevScore = $row_dep['perc'];   
echo $rank;
}
?>
于 2013-07-21T06:42:44.703 回答
-1

问题出在这部分代码中：- SELECT *, IF(@marks = (@marks := score), @auto, @auto := @auto + 1) 您需要确保逻辑正确。

于 2013-07-20T16:40:24.887 回答