![]() The only way to tell the difference between these users is to use their unique ID. Tables are able to relate with each other using unique identifiers.Ī good example of the importance of identifiers is a situation where you have two or more users with the same name performing the same action like buying a product. The table in the last section lacks one of the most important attributes in a relational database - a unique identifier/ID. What are Primary Keys and Foreign Keys in a Relational Database? Using the column names above as examples, we can populate the rows with data like this: John Doe, 02-04-1970, 555-777-999, Earth.Īs you can see above, each row has data that corresponds with its column name. You use rows to populate data in a database table. An example would be a user table with the following columns: Name, Date of birth, Phone, and Country. ![]() The columns denote the specific type of data that can be stored under each respective column. This is because each entity (table) in a relational database can "relate" to another to create more tables which makes the flow of data flexible. The term "relational" is the main characteristic feature that makes relational databases unique. Each table represents a specific object in the database like users, products, orders, and so on. ![]() A relational database is a type of database that stores data in tables made up of rows and columns. ![]()
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