简单的代码超过时间

Question

我写了一段代码来计算病人的等待时间如下;

$query = "SELECT PatientID, Forename, Surname, Gender, Illness, Priority, Arrival_time, TIME_FORMAT(ABS(TIMEDIFF(CURTIME(), Arrival_time)),'%H hours') as Waiting_Time FROM Patient"; 

哪个显示以下数据：如示例所示

PatientID Forename Surname Gender Illness  Priority Waiting Time 
625   Max  Courts M  non-urgent moderate 4 hours 

;等待时间为4小时; 我需要一段代码来检测并提醒time是MORE THAN 4小时;以回应警报。

我试过的示例代码;

if $waitingtime == >4 hours 
then echo "patient must be seen!" 

编辑全码

<?php 

$conn = mysqli_connect("localhost","root","") or die ("No connection"); 
mysqli_select_db($conn, "a&e") or die('Could not select database.'); 

$query = "SELECT PatientID, Forename, Surname, Gender, Illness, Priority, Arrival_time, TIME_FORMAT(ABS(TIMEDIFF(CURTIME(), Arrival_time)),'%H hours') as Waiting_Time FROM Patient"; 
$result = mysqli_query($conn, $query) or die("Invalid query"); 

echo "<table border='1'> 
<tr> 
<th>PatientID</th> 
<th>Forename</th> 
<th>Surname</th> 
<th>Gender</th> 
<th>Illness</th> 
<th>Priority</th> 
<th>Waiting Time</th> 
</tr>"; 

while ($row = $result->fetch_object()){ 

echo "<tr> 
    <td>" . $row->PatientID . "</td> 
    <td>" . $row->Forename . "</td> 
    <td>" . $row->Surname . "</td> 
    <td>" . $row->Gender . "</td> 
    <td>" . $row->Illness . "</td> 
    <td>" . $row->Priority . "</td> 
    <td>" . $row->Waiting_Time . "</td> 
    </tr>"; 

} 

echo "</table>"; 
mysqli_close($conn); 
?> 

Answer 1

我使用mysql_ *为示范开始的目的。你应该使用mysqli_ *或PDO。

$query = "SELECT PatientID, Forename, Surname, Gender, Illness, Priority, Arrival_time, TIME_FORMAT(ABS(TIMEDIFF(CURTIME(), Arrival_time)),'%H') as Waiting_Time FROM Patient"; 

$result = mysql_query($query); 
$row = mysql_fetch_assoc($result); 
if ($row['Waiting_Time '] > 4) 
{ 
    echo "patient must be seen!" 
}