How do I generate an ID with minimum length of 6?

You could use this package or use the primary id and make a method that add's the 000 before the id:

https://github.com/webpatser/laravel-uuid

I'm more so wondering why you'd want to if the ID is running Auto Increment anyway?

A simple str_pad() call should do the trick:

$bookingID = str_pad($id,6,"0",STR_PAD_LEFT);

@option Sometimes you don't want to expose a record's ID.

For example (it's a shitty example, but it's valid):

What if you had a table that houses all paying members? Well you don't really want to expose the ID, because then people know how much your income is etc. All they'd need to do is keep changing the number in the URL until an invalid record is returned. Then they know exactly how many customers you have.

@Eco012390 You’re probably better using something like HashIDs if you don’t want to expose your table’s primary keys.