ALTER

ALTER is a command used in databases to modify existing structures or data. It allows you to change a table's design—such as adding, deleting, or adjusting columns—or update other database objects like indexes or constraints. Think of it as editing a document after initial creation, so the database can evolve as your data needs change without starting from scratch. ALTER ensures your database remains flexible and up-to-date, accommodating updates efficiently while preserving your existing information.