Which type of backup involves copying all data in the database?

A full backup involves creating a complete copy of all the data in the database at a specific point in time. This type of backup captures every piece of data, including tables, stored procedures, and system settings, essentially providing an entire snapshot of the database. The advantage of a full backup is that it allows for a straightforward restoration process since all necessary data is consolidated in one place.

In contrast, incremental backups only save data that has changed since the last backup, while differential backups save data changed since the last full backup. Mirror backups replicate the database in real-time and maintain a copy that mirrors the current state of the database, but they do not create a separate archive of all original data like a full backup does. Thus, the nature of a full backup makes it the correct answer when referring to a backup that involves copying all data in the database.