Generating a random number?

brianb

Hello,

I want to generate a random number / string of number to add to my database entries.

What's the easiest way to generate something random like this?

Any coding examples are appreciated!

Thanks in advance!

m_tt

This might help : )

http://us4.php.net/rand

DisOrDeR1337

If your wanting to like make a unique id you could do this

$UID = crypt(time().$email);
$UID = rawurlencode($UID);
$UID = str_replace(".","",$UID);
$UID = str_replace("/","",$UID);
$UID = str_replace("%","",$UID);

then throw it in the db with say they name

$sql = "INSERT INTO $dbTable (name,uid) VALUES ('".addslashes(fname)."','$UID')";
$result = mysql_query($sql);

Don't know if thats what your wanting to do, but it will create a pretty random value 🙂

Aaron

drawmack

the easiest way to make a unique ID is like this

CREATE TABLE IF NOT EXISTS example (
  ID BIGINT NOT NULL auto_number,
  Field1 VARCHAR(100) NOT NULL,
  PRIMARY KEY (ID)
)

then what you do is on an insert just pretend the field doesn't exist like so

INSERT INTO example (Field1) VALUES ('I'm a deeter head')

Then when you need to pass the ID around in forms and query strings do this

<?php
$eID = md5($ID);

$PHP_SELF?ID=$eID;
?>

When you need to decrypt the ID, it is possible even though md5 is a one way encryption cause watch:

<?php
function un_md5($table,$field,$value) {
    $sql = "SELECT " . $field . " FROM " . $table . " WHERE MD5(" . $field . ")=\"" . $value . \"";
    $result = @mysql_query($sql);

if(mysql_num_rows($result) < 1) {return 0;} //end if

return mysql_result($result,0,0);
?>

To recap:
Step 1) Create an auto_increment field and either primary or unique it.

Step 2) Obfuscate the ID for passing with the md5() function.

Step 3) copy and paste the above function into your script

Step 4) curse at me for not testing my script and just typing it into the message board

Step 5) fix my script

Step 6) never worry about this again and just use the script that you have placed into your global library.

LordShryku

To recap:
Step 1) Create an auto_increment field and either primary or unique it.

Step 2) Obfuscate the ID for passing with the md5() function.

Step 3) copy and paste the above function into your script

Step 4) curse at me for not testing my script and just typing it into the message board

Step 5) fix my script

Step 6) never worry about this again and just use the script that you have placed into your global library.

I'm just going to skip to #4

majiclab

If all you want is a random string, using md5() with something like microtime() is normally pretty good.

Otherwise drawmack's idea is the best, just having an autoincrement primary ID in your database is the best way to go. You wouldn't have to worry about anything, just insert away.

Note: if you have a big table with hundreds of fields, instead of having to list all the fields out that you want to insert, you can just insert them in the order they are in the table...

eg:

ID
Field1
Field2
...
Field100

// you *could* write
INSERT INTO table (Field1, Field2, ..., Field100) VALUES ('Value1', 'Value2', ..., 'Value100')

// but that's a long query to write if you have that many fields
// instead you could do this:
INSERT INTO table VALUES (NULL /* ID */, 'Value1', 'Value2', ..., 'Value100')

But otherwise on small table's, drawmack's INSERT statement is good fun.

Hope one of us got what you were looking for!

-Percy