What are some examples of primary keys in databases?

What are some examples of primary keys in databases?

Primary keys are unique identifiers for records in a database. Examples include user IDs, email addresses, and social security numbers.

Can a primary key be a combination of multiple fields?

Yes, a primary key can be a composite key, which is made up of two or more columns to uniquely identify a record.

What happens if a primary key is duplicated?

If a primary key is duplicated, the database will reject the entry, as primary keys must be unique for each record.

Are primary keys the same as foreign keys?

No, primary keys uniquely identify a record in one table, while foreign keys are used to link records between two tables.