12 · Databases & SQL
Primary Key
A row's unique ID
The unique identifier for each row — its fingerprint — so it can be referred to without ambiguity.
Concrete example
Every user has an “id” primary key; other tables point at it.
A row's unique ID
The unique identifier for each row — its fingerprint — so it can be referred to without ambiguity.
Every user has an “id” primary key; other tables point at it.