plug in for generate Member ID/Student ID

The max is LD9999?
Use the normal database increment and use http://www.php.net/str_pad

PHP Code:

echo 'LD'.str_pad('20', 4, '0', STR_PAD_LEFT); 


what is normal database increment??

Code:

CREATE TABLE Tablename
(
ID int NOT NULL AUTO_INCREMENT
...
)