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What is the difference between a Primary Key and a Unique Key in a database?
Risposta di colloquio
Anonimo
4 gen 2025
: A Primary Key uniquely identifies each record in a table and cannot contain NULL values. A table can have only one Primary Key. On the other hand, a Unique Key also ensures that all values in a column are unique but can accept a single NULL value. A table can have multiple Unique Keys.