ANSI-SPARC Architecture

The ANSI-SPARC Architecture (American National Standards Institute, Standards Planning And Requirements Committee), is an abstract design standard for a database management system (DBMS), first proposed in 1975.

No mainstream DBMS systems are fully based on it (they tend not to exhibit full physical independence or to prevent direct user access to the conceptual level), but the idea of logical data independence is widely adopted.

The objective of the three-level architecture is to separate the user's view: The three levels are: The Three Level Architecture has the aim of enabling users to access the same data but with a personalised view of it.

The distancing of the internal level from the external level means that users do not need to know how the data is physically stored in the database.

This level separation also allows the DBA to change the database storage structures without affecting the users' views.