Computer Science for IGCSE & O level - Databases (Section 2 - No. 42)
What is a primary key used for in a database table?
To store a large block of text.
To uniquely identify each record in the table.
To sort the records in alphabetical order.
To define the structure of the database.
Vysvětlení
A primary key ensures that each record in a table has a unique identifier.