php - MySQL 循环并将变量分配给 PHP 变量

Question

我有一个 MySQL 查询，在 phpmyadmin 中执行时返回正确的结果，但是有谁知道如何使其更加精简(更简单)以及将 $trackNumber 变量附加到 $info['trackName'] 在 PHP while 循环中？

$data = mysql_query(" SELECT 
/* Track 1 */
  ( SELECT 
    tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track1
        WHERE l.leagueID = 1
    ) AS trackName1

/* Track 2 */
, ( SELECT 
    tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track2
        WHERE l.leagueID = 1
    ) AS trackName2

/* Track 3 */
, ( SELECT 
    tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track3
        WHERE l.leagueID = 1
    ) AS trackName3

/* Track 4 */
, ( SELECT 
    tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track4
        WHERE l.leagueID = 1
    ) AS trackName4

/* Track 5 */
, ( SELECT 
    tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track5
        WHERE l.leagueID = 1
    ) AS trackName5

/* Track 6 */
, ( SELECT 
        tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track6
        WHERE l.leagueID = 1
    ) AS trackName6

/* Track 7 */
, ( SELECT 
        tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track7
        WHERE l.leagueID = 1
    ) AS trackName7

/* Track 8 */
, ( SELECT 
        tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track8
        WHERE l.leagueID = 1
    ) AS trackName8

/* Track 9 */
, ( SELECT 
        tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track9
        WHERE l.leagueID = 1
    ) AS trackName9

/* Track 10 */
, ( SELECT 
        tr.trackName
        FROM league l 
        INNER JOIN tracks tr ON tr.trackID = l.track10
        WHERE l.leagueID = 1
    ) AS trackName10

FROM league 
WHERE leagueID = 1 ");

$trackNumber = 1;

while($info = mysql_fetch_assoc( $data )) {

echo "<div class=\"col-lg-3\" align=\"center\">\n";
echo " <h5> <hr/>Track " . $trackNumber  . "<hr/></h5><p>" . $info['trackName['$trackNumber']'] . "</p>\n";
echo " </div>\n";

$trackNumber++;

}

Answer 1

您的查询仅返回一行，您不应在循环中调用mysql_fetch_assoc()。要访问特定轨道编号的列，您需要使用字符串连接来生成数组键: $info['trackName' 。 $trackNumber]

$info = mysql_fetch_assoc($data);

for ($trackNumber = 1; $trackNumber <= 10; $tracknumber++) {
    echo "<div class=\"col-lg-3\" align=\"center\">\n";
    echo " <h5> <hr/>Track " . $trackNumber  . "<hr/></h5><p>" . $info['trackName' . $trackNumber] . "</p>\n";
    echo " </div>\n";
}