PHP - Generating unique number for database field

[spaceman12]

Hey guys,

I m not yet an experienced coder. SO faced alot of problems. Here, I'm trying to generate a UNIQUE RANDOM NUMBER set between two numbers. Repetative occurance must be avoided by all means as I want every number so generated bears a unique value. In other words, every values that made entry into the field of my database should be differant from each others.

 

 

<?php
$conN=mysql_connect("localhost","root","");
if(!$conN)
{
die('error'.mysql_error());
}
mysql_select_db("freebie_allusers",$conN);
$UIN=mt_rand(1,5);
$locateUIN="SELECT UIN FROM user_info WHERE UIN='".$UIN."'";
$fetchUIN=mysql_query($locateUIN);
$resultUIN=mysql_num_rows($fetchUIN);
if($resultUIN>0)
{



WHAT CODE IS REQUIRED HERE SO AS TO GENERATE UNIQUE RANDOM NUMBER?






}

else 
echo $UIN;
?>

 

Thanx in advance

[msaz87]

You can use auto increment for a key column in the table and every row will automatically increase -- therefore it'll always be unique.

 

If you want to generate one, you already used mt_rand and that and rand are probably the way to go -- unless I'm not quite understanding what you're trying to do?

[jaikob]

use rand().

 

<?php $random_number = rand(); ?>

 

To be specific about the number length, read the manual entry for rand on php.net.

 

What a lot of people do is create an id field and set it as a primary key with auto increment enabled. That way you don't even have to mess with the id. But you have stated you don't want repetition. The reason a lot of others do this is because with rand you always have the slight possibility of trying to insert a number you have already used. Especially if your using a primary key.

[spaceman12]

Those generated numbers will serve as a primary Identification code for all users and it should be auto generated by the server itslef.  All the number so generated will bear a modulo of some number  which i can set it later on but what i'm trying to do at this stage is to abstain the events of recording the same value of number in the database field.