php - 与 MySQL 数据库链接的 html 搜索表单

Question

我是 PHP 和 MySQL 的新手，很难根据包含多个字段的 html 搜索表单从数据库中提取数据。 1st 字段(*必填)= 选择选项(选择名称 = area_name )，2nd = 输入类型:学校名称，3rd =日期，4-5 日 = time_from，time_to。问题:如何根据上述字段提取讲师姓名？

下面是 PHP 代码(忽略数据库连接，它正在工作):

<小时/>

    if (!empty($_REQUEST['term'])) {
    $term = mysql_real_escape_string($_REQUEST['term']);     

    (line 8)
    $sql = mysqli_query("SELECT lecturer_name, city, phone, e-mail * FROM 
    area_name where area_name LIKE '$search'") UNION ("SELECT * FROM school 
    where school_name LIKE '$search'") UNION ("SELECT * FROM schedule where 
    date LIKE '$search'") UNION ("SELECT * FROM schedule where time_from 
    LIKE '$search'") UNION ("SELECT * FROM schedule where time_to LIKE 
   '$search'");
    $r_query = mysqli_query($sql); 

    echo "<table border='1' cellpadding='5'>";
    echo "<tr> <th>Lecturer Name</th> <th>City</th> <th>Phone</th> 
    <th>Email</th> <th></th> <th></th></tr>";

    // loop through results of database query, displaying them in the table
    while ($row = mysql_fetch_array($r_query)){

            // echo out the contents of each row into a table
            echo "<tr>";
            echo '<td>' . $row['lecturer_name'] . '</td>';
            echo '<td>' . $row['city'] . '</td>';
            echo '<td>' . $row['phone'] . '</td>';
            echo '<td>' . $row['email'] . '</td>';
            echo "</tr>"; 
    } 

    // close table>
    echo "</table>"; 

    }

    $conn->close();

结果出现如下错误:

Parse error: syntax error, unexpected 'UNION' (T_STRING) in D:\XAMPP\htdocs\trv\search_lecturer.php on line 8

我不知道如何将 html 字段名称与 mysql 连接起来。非常感谢任何帮助!

Answer 1

UNION 是 SQL 运算符，而不是 PHP。您的 PHP 语法有错误。

$sql = mysqli_query("(SELECT .....) UNION (SELECT .....) UNION .....");

附注* 表示所有字段，如果指定字段，* 不是必需的。