This was a question that came up with the ninth digit news on the phones here in Brazil.
I have in the system a list of phones that are saved together with the DDD.
How can I make an 8-digit phone (and with the DDD) be filled with 9?
Example of how it is saved in the database:
(31)9915-2855
How could I turn it into (31)99915-2855
Note : I accept both PHP and MySQL solutions.