Q 8,paper 3.J 12.Which level of Abstraction describes what data are stored in the Database ?

Options (A) Physical level (B) View level (C) Abstraction level (D) Logical level
Answer(D) Logical level or conceptual level.
Physical Data Level
The physical schema describes details of how data is stored: files, indices, etc. on the random access disk system. It also typically describes the record layout of files and type of files (hash, b-tree, flat).
Conceptual Data Level
Also referred to as the Logical level Hides details of the physical level.Conceptual Level represents the entire database. Conceptual schema describes the records and relationship included in the Conceptual view. In the relational model, the conceptual schema presents data as a set of tables.The DBMS maps data access between the conceptual to physical schemas automatically. • Physical schema can be changed without changing application: • DBMS must change mapping from conceptual to physical. • Referred to as physical data independence. External Data Level
In the relational model, the external schema also presents data as a set of relations. An external schema specifies a view of the data in terms of the conceptual level. It is tailored to the needs of a particular category of users. Portions of stored data should not be seen by some users and begins to implement a level of security and simplifies the view for these users