An important advantage of database management systems is Data Independence. Data Independence refers to the insulation from applications programs from changes in the way the data is structured and stored. Levels of Abstraction in a DBMS graph TD F(fa:fa-table View 1)---E G(fa:fa-table View 2)---E H(fa:fa-table View 3)---E["fa:fa-database Conceptual Schema"] E---A["fa:fa-server Physical Schema"] A---B["fa:fa-HDD-o Disk"] Logical Independence If the structure of the data changes, applications and users can be insulated from this changes thanks to external schemas (in SQL, views).
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A data model is a collection of descriptions of the data and it’s relationships that hides details of the storage implementation. A database management system such as PostgreSQL or MS SQL allows users to define data models. The relational data model is a particular type of data model. A more abstract data model is the semantic data model. It is usually used to develop an initial description of the data in a real world scenario, like a business or any other real world organization.
DBMSs have the following advantages: Data Independece, Efficiency, Data Integrity, Centralized Administration and Reduced Application Development Time