Hi,
I am trying to generate a non-sequential random alphanumeric value.
Just to make things fun, I need to guarantee that each value is unique.
I have a working solution, but it seems retarded to me because there
is a small chance that 2 people might hit the same page at the same
time, do separate inserts, but both get the same MAX(uiIndex) value.
Is there a better way to do this?
TIA,
Craig
table defn:
create table randomKey (
uiIndex int unsigned auto_increment not null primary key,
cKey char(20) unique
);
function getKey() {
//get random number into db. it is guaranteed
//unique from db once result = true because
//cKey is unique
$query = 'INSERT INTO randomKey (cKey) VALUES (RAND())';
while (!$result = mysql_query($query, dbConnect($errorMsg))) {
//do nothing, just loop until result = true
}
//now get the random number, and MD5 it to get it alphanumeric
$query = 'SELECT MAX(uiIndex), cKey FROM randomKey GROUP BY cKey';
$result = mysql_query($query, dbConnect($errorMsg));
$row = mysql_fetch_object($result);
return md5($row->cKey);
}
--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php
