Limiting Database entries in PHP/MYSQL

[jonasgalileo]

i have a whole script that can limit database entries coming from user inputs or data.

but i have encountered an error:  Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in C:\wamp\www\Thesis Lc Advance Black Version\reservation_monday.php on line 30..

 

is my code for limiting entries correct near the mysql_numr_rows()part?

 

 

<?php

 

//Database connection

require_once("connection.php");

 

if(isset($_POST['submitmondaystudent'])) {

$fullname = addslashes(strip_tags($_POST['fullname'])); //field name title

$email = addslashes(strip_tags($_POST['email'])); //field name title

$reasons = addslashes(strip_tags($_POST['reasons'])); //field name title

$hour1 = addslashes(strip_tags($_POST['hour1'])); //field name title

$hour2 = addslashes(strip_tags($_POST['hour2'])); //field name title

$sched1 = addslashes(strip_tags($_POST['sched1'])); //field name title

$minutes = addslashes(strip_tags($_POST['minutes'])); //field name title

$programs = addslashes(strip_tags($_POST['programs'])); //field name title

$instructor = addslashes(strip_tags($_POST['name'])); //field name title

$date = addslashes(strip_tags($_POST['date'])); //field name title

 

 

// insert items to database;

$insert = "INSERT into monday_students(startingtime,endingtime,sched,minutes,programs,instructor,fullname,email,reasons,date)

  values('$hour1','$hour2','$sched1','$minutes','$programs','$instructor','$fullname','$email','$reasons',('$date'))";

 

 

$result = mysql_query($insert) or die(mysql_error());

 

$limit = 4;

 

if ($result)

{

  if(mysql_num_rows($result) == 4) {

 

?>

<script type="text/javascript">

alert("Your only allowed to register 4 subjects.");

self.location="monday_reservation.php"

</script>

<?php

}

else

{

?>

 

<?php

 

$sendto = $email;

$ccto = "[email protected]";

$subject = "Monday Schedule Confirmation";

$message = "Welcome " . $_POST['fullname'] . " 

Thank you  for registering in our Site.

 

Your Monday Schedule information :

    Time : ".$_POST['hour1'].":".$_POST['minutes']." - ".$_POST['hour2'].":".$_POST['minutes']." ".$_POST['sched1']."

    Subject : " . $_POST['programs'] . "

    Instructor : " . $_POST['name'] . "

 

Visit our tutorial center for more details or contact us at 305-4355";

$header = "From: www.lcadvancedavao.com\r\n";

$header .= "[email protected]\r\n";

mail($sendto, $subject, $message, $header); 

 

echo" Your Reservation has been sent to our staff database,<br/>Check your email address for more updates.<br/>

<a href=tutorial_reservation.php>Return to Registration page</a> | <a href=schedule_reservation.php>Return to Previous Page</a>

<br/><br/>

";

}

}

 

 

}

[rhodesa]

The only thing I can think of is that an INSERT doesn't return a result. Are you looking to limit a particular email address from inserting more then 4 entries? If so, you should do a SELECT first, then the insert if there are less then 4 entries

[waterssaz]

Hi, mysql_num_rows() will not work when your sql query $result comes from an insert statement. You need to use mysql_affected_rows() instead. Hope this helps :-)

PS. I will assume that you have already set the link identifier for the second parameter for your mysql_query() elsewhere in your script in a mysql_connect().