Question

我有一个叫做分组的表。因此，当我注册新组时，如果组具有与现有组相同的时间和房间号，则系统应该警告它。这是我的代码，但它不起作用。拜托，帮助我！

$query1= mysql_query("SELECT * FROM grouping WHERE room_number ='$room_number' AND week_days='$week_days' AND time='$time'");
if(mysql_num_rows($query1) != 0 ) { //CHECK FOR EXISTING TIME AND NAME IN TABLE
  mysql_query("INSERT INTO grouping(name, subject, status, week_days, time, room_number, tutorID)
               VALUES('$name','$subject','$status','$week_days','$time','$room_number','$tutorID')"); 
  echo "<script>alert('Your group is registered')</script>";
  echo "<script>window.open('tutor_main.php','_self')</script>";
} else {
  echo "<script>alert('This time is not available')</script>";
  echo "<script>window.open('tutor_main.php','_self')</script>";
  exit();
}

Answer 1

我假设您正在尝试测试$ room_number，$ week_days，$ time的值是否已经在'grouping'表中。根据这个假设，这是我建议的方法：

//# Assuming the values we want to test are $room_number, $week_days, $time:
$query1= mysql_query("SELECT * FROM grouping WHERE room_number='$room_number' AND week_days='$week_days' AND time='$time'");

//# Logically if zero rows comes back you are free to insert the data in the database.
if(mysql_num_rows($query1)==0) 
{ 
    //# THIS CREATES A NON DUPLICATE RECORD WITH UNIQUE VALUES FOR $room_number, $week_days, $time:
      mysql_query
        (
            "INSERT INTO grouping(name, subject, status, week_days, time, room_number, tutorID)
            VALUES('$name','$subject','$status','$week_days','$time','$room_number','$tutorID')"
        );
    echo "<h2>Your data was added to the database successfully!</h2>";
}
else
{
    //# THE QUERY RETURNED MORE THAN ZERO ROWS - YOU HAVE A CONFLICT IN THE DATA
    echo "<h2>ERROR! You have a conflict in the data</h2>";
}

我希望这有助于您开始朝着正确的方向前进。

检查表中是否存在多个值

1 个答案: