If I follow you correctly, is the scenario below possible.?? Let's say there are 2 users accessing the app at the same time (user A and B). Here's the sequnce of operation... 1. user A insert into table (get id = 1 from auto increment value) 2. user B insert into table (get id = 2 from auto increment value) 3. user A get value from $id = LAST_INSERT_ID() (id = 2) 4. user B get value from $id = LAST_INSERT_ID() (id =2) 5. user A update table where id = 2 6. user B update table where id = 2 in the scenario above, the row with id = 1 doesn't get his file number (fin) while the row with id = 2 gets the value for his file number twice... How can we make sure that those 3 processes are atomic operation (insert table -> get id from LAST_INSERT_ID() -> update table) ?? Thanks.. tedd-2 wrote: > > For example, I would use (not tested): > > // code to create a record (i.e., INSERT INTO your_table (whatever) > VALUES ('$whatever') ) > > $id = LAST_INSERT_ID(); > > The above statement finds the last record added to the database (the > index of the record) and then I would create my application-number > and store it in that record -- like so: > > // code to create the application-number (i.e., $application-number = > 'AAA' . $id; ) > > $query = "UPDATE your_table SET application_number = > '$application_number' WHERE id = '$id' "; > $result = mysql_query($query) or die('Error, query failed'); > > That way you should not have any duplications and you have > application-numbers (as you want )that are tied to the auto-numbering > of the table's index. > > HTH's > > tedd > -- > ------- > http://sperling.com http://ancientstones.com http://earthstones.com > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > > > -- View this message in context: http://www.nabble.com/Creating-alphanumeric-id-for-a-table-tp25391939p25447945.html Sent from the PHP - General mailing list archive at Nabble.com. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php