Auto generate ID

PHP
1

my registration table:

Reg_Id bigint 255
Reg_CreatedFor text 0
Reg_UserName varchar 15
Reg_Password varchar 12
Reg_ConfirmPwd varchar 12
Reg_Name text 0
Reg_Email varchar 30
Reg_Gender text 0
Reg_DOB date 0
Reg_Religion varchar 20
Reg_MotherTongue varchar 75
Reg_Country varchar 20

Reg_Id is auto-increment and primary key as i declared…
it increment 1,2,3 like this

but i want add some values before Reg_ID…
example if i want add C100+Reg_Id…

i want this auto generate id…
how can i do this…

pls help me

2

This is a MySQL question.

I don’t think you can do that.
What you can do (I think), is add another column to the table and put the ‘C100’ value in it, and define both fields as primary key.