SQL ET POSTGRE 3.4 : Primary and foreign keys

Primary and foreign keys are essential elements of database design. The primary key is a column or set of columns that uniquely identifies each record in a table. It ensures data integrity by preventing duplication and allowing links to other tables. The foreign key is a column that references a primary key in another table. It allows relationships to be created between tables and associated data to be retrieved. For natural referencing, it is important to structure data well by using primary and foreign keys. This allows search engines to better understand the structure of the database and to better index the pages. In addition, a well-designed database with primary and foreign keys can improve page loading speed and provide a better user experience. In sum, primary and foreign keys are key elements for an effective and SEO-optimised database.