Eternal Loop?

[EmperorJazzy]

Howdy,

 

I'm utilising a random number as an ID for each new object created. At the creation stage (input to database tables), I'm wishing to check that the new random number doesn't already exist. Here is my code;

 

Field 'ListID' is a varchar field

 

		while ($listid='')
		{
			$listtest = rand(1000000000,9999999999);
			$query = "SELECT ListID FROM tblUserList WHERE ListID='" . $listtest . "'";
			$result = mysqli_query($dbc, $query) or die('Error checking ListID - ' . $query);
			$row_cnt = mysqli_num_rows($result)
			If ($row_cnt=0)
				{
				$listid=$listtest;
				}
		}

 

The code is not executing; essentially, there are no error returns and the page continues to sit idly waiting for something to return. Is this loop ot logical?

[Nuv]

Can you please Try this

 

<?php
				If ($row_cnt == 0) // use double == here
				{
				$listid=$listtest;
				}
?>

 

One = is used for assigning values and == is used for comparing

[EmperorJazzy]

So...

 

<?php

		while ($listid='')
		{
			$listtest = rand(1000000000,9999999999);
			$query = "SELECT ListID FROM tblUserList WHERE ListID='" . $listtest . "'";
			$result = mysqli_query($dbc, $query) or die('Error checking ListID - ' . $query);
			$row_cnt = mysqli_num_rows($result)
			If ($row_cnt==0)
				{
				$listid=$listtest;
				}
		}

?>

 

Should I also use the == for the while statement?

<?php

  while ($listid=='')

?>

[Nuv]

No don't use == for while. Only for if.

Try it and check if it works. (I am considering there is more to your code.)

[DavidAM]

One = is used for assigning values and == is used for comparing

 

YES! Use == for that while loop as well.