Question

a table can have only one primary key

Answer 1

Answer:

Yes, this is true that a table can have only one Primary key because it is unique and identical.

Answer 2

Answer:

You can have only one primary key, but that can consist of as many columns as you need to uniquely identify your rows. where P_Td and LastName are columns in your table. If you think you want more than one primary key, then the answer is "not really." You can have only one primary key