generating random codes

Posted on 16th Feb 2014 07:03 pm by admin

Hi guys n gals,

I have a requirement to generate 250,000 unique codes...

These codes are for a tracking service and will be stored in the database (table field has a unique index).

Now I am working on the assumption this must work on the command line as the script will take a long time to complete... here is the salient pat of my code...

Code: <?php
...
function appendToCode( &$val , $key , $append )
{
$val = $val . $append;
}

$chars = "ABCDEFGHJKLMNPQRSTUVWXYZ";
$charend = strlen ( $chars );

$date = date ( 'md' );

$month = $date[0].$date[1];
$year = $date[2].$date[3];

$datecode = $chars[$month] . $chars[$year[0]] . $chars[$year[1]];
$codes = array();
$no_codes = isset( $_GET['no_codes'] ) ? $_GET['no_codes'] : 250000;
$codecount = 0;

do
{
for ( $j = $codecount ; $j < $no_codes ; $j++ )
{
$trackcode = NULL;
for ( $i = 0 ; $i < 7 ; $i++ )
{
$trackcode .= $chars[rand( 0 , $charend - 1 )];
echo ( time() - $start ) . PHP_EOL;
}
$codes[] = $trackcode . $date;

}
//$t = count($codes);
//echo 'Codes Generated: ' . $t . PHP_EOL;
//echo 'Last Code: ' . $codes[--$t] . PHP_EOL;

$codes = array_unique( $codes );
$codecount = count ( $codes );

//echo 'Unique Codes: ' . $codecount . PHP_EOL;
// the following statement prevents infinite loop in dev mode...
if (
(time() - $start) > 150
)
{
break;
}


} while ( $codecount < ($no_codes) - 1 );
...
The last characters of the code relate to the date - as these codes will only be developed every now and then - not a frequent occurrence and will allow a check on the database to see if codes ending in that 3 character string exist...

What I am asking is, is there a more efficient method of performing this operation.

Any tips would be most welcome.

Your Answer:

Login to answer

Other forums

How to replace search button with link?
hi to everbody.
i have a search submit form and button like this :

<form id="f

How to schedule the a job?
Hi,
I have prepared a task ( i.e. a procedure is prepare the file and send the same to con

Two fgetcsv related questions ;D
First of im trying to get a file from a merchants server but the directory is protected, I know the

Need help: how to catch acess of undefined class properties
Hello. I am learning OO with PHP and have hit a problem.
Some code runs as perfectly valid code,

Basic Question about Threading and PHP...
I have a page that I am working on and it is taking several hours to process. The basics of what th

Interpret Order
Hello all,

I'm wondering if I have this:

Code: $switch = array(
'one' =>

php/xmlrpc class issue
I am working on xml-rpc in php to start with.

I have a class that only has variables defined

Help with PHP and checkboxes
I am posting this for a friend of mine, i wrote a small script for her to process her form data to a

Multiple websites question.
Hi, does php have any functionality that enables a programmer to extract information from a website

Encrypt php code?
Is it possible to encrypt php code in files,
so that it displays a load of unreadable characters