Introduzindo SQL

SQL is a programming language used to manage and manipulate data within RDBMS, allowing users to retrieve, update, and delete information. Based on Edgar F. Codd's tabular structures, it utilizes aggregate functions to derive summarized values from multiple rows. To ensure data integrity, SQL employs constraints like PRIMARY KEY, which combines NOT NULL and UNIQUE requirements. These rules provide a critical protection layer within the database, independent of the application layer accessing the data.