Keywords, primary keys, candidate keywords

Keywords, primary keys, candidate keywords

In a two-dimensional table, a combination of a field or several fields that uniquely determines a record is called a "super keyword". A "super keyword" can uniquely determine a record, but the fields it contains may be redundant.

If a super keyword removes any of these fields and no longer uniquely determines the record, it is called the candidate keyword.

A candidate keyword can uniquely determine a record, and the fields it contains are the most refined. This means that the candidate keyword is the simplest super keyword.

A primary key (primary key) is one or more fields in a table whose values are used to uniquely identify a record in a table.