external level
The machine level.
how data are stored would be in a physical layer
Physical abstraction in data abstraction refers to hiding the implementation details of how data is stored and accessed. It allows programmers to work with high-level concepts of data without needing to understand the underlying physical structures. This separation enhances modularity and simplifies the complexity of software systems.
abstraction is show nonessential data to user ,
Data abstraction is the reduction of a body of data to a simplified representation of the whole. Data abstraction is usually the first step in database design in order to create a simplified framework that can be added to in order to complete the database.
The three levels of data abstraction in a DBMS are physical, logical, and view. Physical level: Describes how data is stored in the database, including details like data storage and access paths. Logical level: Focuses on the structure of the data in the database, including schemas, tables, and relationships. View level: Represents how users view the data, providing a customized and simplified representation of the data to different user groups.
no
Data Abstraction in DBMS means hiding implementation details(i.e. high level details) from end user.e.g. In case of storage of data in database user can only access the database, but implementation details such as how the data is stored phisically onto the disc is hidden from user.
Physical level: The lowest level of abstraction describes how a system actually stores data. The physical level describes complex low-level data structures in detail.Logical level: The next higher level of abstraction describes what data the database stores, and what relationships exist among those data. The logical level thus describes an entire database in terms of a small number of relatively simple structures. Although implementation of the simple structures at the logical level may involve complex physical level structures, the user of the logical level does not need to be aware of this complexity. Database administrators, who must decide what information to keep in a database, use the logical level of abstraction.View level: The highest level of abstraction describes only part of the entire database. Even though the logical level uses simpler structures, complexity remains because of the variety of information stored in a large database. Many users of a database system do not need all this information; instead, they need to access only a part of the database. The view level of abstraction exists to simplify their interaction with the system. The system may provide many views for the same database.
health
Abstraction: Abstraction refers to removal/reduction of irrelevant data or unnecessary data or confidential data from a Class. Data hiding: Data hiding is a feature provided by the abstraction for hiding the data from the class.
three levels of data abstraction are: 1. Physical level : how the data is stored physically and where it is stored in database. 2. Logical level : what information or data is stored in the database (like what is the datatype or what is format of data. 3.View level : end users work on view level. if any amendment is made it can be saved by other name. for the database to be usable it must retrieve data efficently.this efficency led designer to use complex data structure in the database