i want to build a data base software that will accept inputs but will not accept duplications?

Question

A database software that will accept all personal datas including duplicated names but will not accept two identity numbers, it will display the already exisiting records of the same identity numbers inputed.

Answer 1

MS Access can be set up to create unique identifiers for every entry.

Answer 2

what database are you using?
on most(if not all) databases , you can spaecify that the value that is being put in is unique (not repeated on any other records)