In PHP/MySQL, what's the best way to generate a unique reference ID so that when a person submits his info to the database, he gets a reference number to follow up with his request?
I am already using the auto-increment feature from the database since the data needs to be unique every time a user submits information, but then I need to pick that specific data from the database in order to retrieve that incremented value and display it with PHP.
rexem's comment is correct; then if you're using the basic mysql commands in PHP, you can use
$id = mysql_insert_id()
to retrieve the last insert'ed row's ID number (based on the primary key of that table).
Hi,
I would probably go with the auto_increment field that you already have : it's a solution that works fine -- maybe concatenating it with something, to get, for instance "CMD123456", which is more "human-readable".
To get the last generated auto_increment for the currently active connection to the DB, you can use the mysql_insert_id function -- provided you are working with the family of mysql_* functions.
Just call it after you have done your insert query, and it'll get you the value of the auto_increment that has been generated by/for that one.
If using mysqli_*, you'll need mysqli_insert_id, and, if using PDO, you'll work with PDO::lastInsertId.
If you want to use the auto_increment value you can execute select last_insert_id() after your insert.
last_insert_id() is a mysql function that returns the auto increment value from the last insert.
As others have noted some mysql libraries provide their own method for getting the last insert id