A primary key in SQL is a unique identifier for a record in a table. It ensures that each entry is distinct and helps maintain data integrity by preventing duplicate…
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Can you explain what a primary key is in SQL and why it is important?
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Can you explain what a primary key is in SQL and why it’s important?
A primary key in SQL is a unique identifier for a record in a table. It’s important because it ensures that each record can be uniquely retrieved and is critical…
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Can you explain the differences between primary and foreign keys in a database and their importance in data integrity?
A primary key uniquely identifies a record in a table, while a foreign key establishes a link between two tables by referencing a primary key in another table. They are…
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