What is a foreign key and how does it help in querying data?

< 1 min read

A foreign key is a column that links a record in one table to a primary key in another table.
It defines the relationship between related tables like orders and customers.
This helps join data accurately across tables during queries.
In my project, customer_id was a foreign key in the sales table.
It allowed us to pull customer details along with transaction data.
Foreign keys also help maintain data integrity by preventing invalid references.
They make complex analytical queries more structured and reliable.

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