Question

我正在制作一个酒店数据库，并写了一个查询，该查询应打印出某段时间内所有可用的房间，但是当我运行它时，它不打印任何东西。它使用表格预订和房间的信息。这是php代码，以及html代码。有人可以告诉我这里我做错了吗？

<HTML>
        <head> </head>
        <body>
        <h3>Choose the period to see which are the free rooms:</h3>
        <form action="query2.php" method ="GET"><br>
        <fieldset>
        <div class="field">
        <div class="pick-date">
        <label for="date_from"></label>
        From:&nbsp;&nbsp;&nbsp;&nbsp;<input type="date" name="a"> 
        <br/><br/>                    
        <div class="field">
        <label for="date_to">
        To:&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;<input type="date" name="b">
                        </label>
                   </div> <br/> 
        <div class="field">
          <label for="room_type">
        Room type:
        <select name="room type[]">
        <option></option>
        <option>Classic single</option>
          <option>Superior single</option>
          <option>Classic double</option>
          <option>Superior double</option>
          <option>Vip room</option>
          <option>Family room</option>

        </select>
        <br/><br/> 
        <input type="submit" name="submit" value="Submit">
        </form>
        </body>
        </html>

<?php

$x = isset($_GET['room type[]']);
        if (!isset($_GET['a']))
     {$a = null; }
        elseif (!is_string($_GET['a'])) {
        $a = false;
        } else { $a = $_GET['a'];
        }
        $b = isset($_GET['b']) && is_string($_GET['b']) ? $_GET['b'] :'';
        $query=mysql_query(
        "select  r_id, r_type, r_price
        from Rooms
        WHERE r_type='$x' and r_id not in 
        (select b_rooms
                  from booking
        where (b_checkin >= '$a' and b_checkin < '$b')
                    or (b_checkout >= '$a' and b_checkout < '$b'));" );
        if (!$query) {
            $message  = 'Invalid query: ' . mysql_error() . "\n";
            $message .= 'Whole query: ' . $query;
            die($message);
        }
        while ($row = mysql_fetch_assoc($query))
         {
            echo $row['r_type'];
        echo"&nbsp; &nbsp;";
            echo $row['r_price'];
        echo"&nbsp; &nbsp;";
            echo $row['r_id'];
        echo"<br>";}
        mysql_free_result($query);
        ?>

为什么我的查询没有打印出来？

0 个答案: