generate an automated Number inserting to formView

Question

I'm developing HRIS that has many functions include attendance storage as shown in table:

 

 

Attendance ID	Employee ID	Date	Present
INT (PK)	INT (FK)	DD/MM/YYYY	BIT (checkBox)

 

 now i'm thinking to set Attendance ID to be generating automatically by increasing one to avoid conflicting as long as it's primary key.

 

 

 

then I need to see attendance on another table of specific date clicked in celendar control.

 

any code available to reference on it?

thanks