6JOINING TABLES IN A RELATIONAL DATABASE
In Chapter 1, I introduced the concept of a relational database, an application that supports data stored across multiple, related tables. In a relational model, each table typically holds data on one entity—such as students, cars, purchases, houses—and each row in the table describes one of those entities. A process known as a table join allows us to link rows in one table to rows in other tables.
The concept of relational databases came from the British computer scientist Edgar F. Codd. While working for IBM in 1970, he published a paper called “A Relational Model of Data for Large Shared Data Banks.” ...
Get Practical SQL now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
