Learn More About Relational Databases
R2026bA relational database is a collection of data organized into tables with predefined relationships. These relationships connect tables, showing how different data elements relate.
The catalog is the top-level container for data in a relational database and can contain multiple schemas, each grouping related tables. Within each schema, tables store data in rows and columns, where rows represent records, and columns define data types such as text, numbers, or dates. Each table has a primary key that uniquely identifies rows. Primary keys enable relationships between tables through foreign keys, which reference primary keys in other tables. For more information on using primary and foreign keys, see Link Relational Tables Using Primary and Foreign Keys.
For example, a bookstore owner can use a database to track operations. A typical catalog might include schemas that organize sales and product data, each containing tables for customers, orders, inventory, and items. To associate a customer with an order, the owner can use a foreign key that links to the customer ID in the customers table. These relationships enable the owner to generate summary reports, such as identifying customers who purchased a specific item on a given date.
