What makes a good or bad primary key in a database?
What is a primary key?
In the world ofdatabases, the primary key of a relational table uniquely identifies each record in the table.
Glowimages / Getty Images
Databases use keys to compare, sort, and store records, and to create relationships between records.
Choosing the primary key in a database is one of the most important steps in the process.
Primary keys may consist of a single attribute or multiple attributes in combination.
Primary keys are the unique links to related information in other tables where the primary key is used.
It must be entered when a record is created, and it should never be changed.
Each table in the database has a column or two specifically for the primary key.
The student’s unique student ID number is a good choice for a primary key in the STUDENTS table.
Some people don’t even have a Social Security Number.
However, because both of those cases are rare.
Social Security Numbers can be a good choice for a primary key.
Just remember:
FAQ
It’s the same as in a database.
