From the course: Relational Databases Essential Training
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Use primary keys to identify records
From the course: Relational Databases Essential Training
Use primary keys to identify records
- [Narrator] Relational databases only work if the system can uniquely identify each record in a table. They do this using a column that's been designated as the table's primary key. Primary keys are used everywhere in our daily lives. Your library card number or bank account number are the primary keys to your accounts. Your email address is often used by websites to uniquely identify you from every other user, and it acts as the primary key for retrieving your shopping history or your social media posts. The government uses your social security number and driver's license numbers to make sure that you've paid your taxes, and verify eligibility for benefit programs. These unique identifiers are all critically important to the functionality of the systems that you participate in. Beyond the databases that identify you as a unique person, businesses need to have unique product numbers so that they ship the correct items to…
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