PRIMARY KEY vs UNIQUE KEY vs FOREIGN KEY-Part 2 | UNIQUE KEY CONSTRAINT | UNIQUE KEY vs UNIQUE INDEX

PRIMARY KEY vs UNIQUE KEY vs FOREIGN KEY - Part 2 | UNIQUE KEY CONSTRAINT | UNIQUE KEY vs UNIQUE INDEX PRIMARY KEY vs UNIQUE KEY, PRIMARY KEY vs FOREIGN KEY, PRIMARY KEY Constraint vs UNIQUE KEY Constraint, PRIMARY KEY Constraint vs FOREIGN KEY Constraint, Index vs Key, Unique Key vs Unique Index, Unique Clustered Index, non-clustered index, composite key, candidate key, alternate key, HEAP in SQL, Key vs Index, WITH CHECK vs WITH NOCHECK FOREIGN KEY Constraint, Non-clustered PRIMARY KEY, Clustered Unique Key, PRIMARY KEY vs UNIQUE KEY vs FOREIGN KEY, PRIMARY KEY Constraint, UNIQUE KEY Constraint, FOREIGN KEY Constraint Agenda: ------------- QA. What is the difference between PRIMARY KEY and UNIQUE KEY? QB. What is the difference between PRIMARY KEY and FOREIGN KEY? QC. What is the difference between UNIQUE KEY and UNIQUE INDEX?