SELECT查询不返回任何内容

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                    <p class="mb0 mt6">Closed <span title="2015-05-01 04:59:28Z" class="relativetime">4 years ago</span>.</p>
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If I print variable $q, the result is okay. If I write $q='some_subject'; query returns the right answear. But, if I use it like in the code(value stored in q is from $_GET), nothing is returned (q is value which i get from selection on a dropdown list)

$q = $_GET['q'];

$query= "SELECT * FROM list WHERE subject='".$q."' ";

$result = mysqli_query($link,$query);

if($result) {
    while($row = mysqli_fetch_assoc($result)) {

echo $row['prof_name'];
echo $row['prof_email'];    
    }
}

mysqli_close($link);

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Answer 1

try this.

$query= "SELECT * FROM list WHERE subject = '{$q}'";