Oracle Instance Explained: Key Components

An Oracle instance refers to a collection of Oracle database processes running on a server. Each instance consists of background processes and memory structures, including the SGA (System Global Area) and background processes, used to manage the operation and maintenance of the database. Each Oracle database can have one or more instances, with each instance corresponding to a database. Each instance has its own SGA and background processes, but they can access the same database data files. Instances serve as an intermediate layer between the database users and the database, responsible for handling user requests, managing database objects, and maintaining the consistency of the database.