You need to state what your options are!
It is important that the data for the primary key are unique, and will remain unique in the future.
Database designers will typically play it safe and just use an auto-increment integer field as the primary key, so that there is never any doubt which row is being worked on. Even then, you need to consider how large to make the primary key; even a 32-bit unsigned integer may not be enough eventually!
It is important that the data for the primary key are unique, and will remain unique in the future.
Database designers will typically play it safe and just use an auto-increment integer field as the primary key, so that there is never any doubt which row is being worked on. Even then, you need to consider how large to make the primary key; even a 32-bit unsigned integer may not be enough eventually!
