Abstraction means “hiding”. In Data Base Management System (DBMS), Data abstraction is the process of providing a simplified interface to a more complex system, while hiding the underlying implementation details. It involves separating the essential features of a system from the non-essential details and representing the essential features in a way that is easy to understand and manipulate.
Another definition of Data abstraction is, it is the process of hiding certain details and showing only essential information to the user. It aims to reduce complexity and increase the manageability of a system by providing a simplified view of the system that is easier to understand and work with.
Data redundancy is the duplication of data within a database. It occurs when the same data is stored in multiple locations within a database, or when multiple copies of a database are created. Data redundancy can lead to inconsistencies, as different copies of the data may not be kept in sync, and it can also waste storage space. However, it can also provide some benefits, such as improving the reliability and availability of the data.
In other words, Data redundancy is the duplication of data within a database. It can occur when the same data is stored in multiple places or when multiple copies of the same data are stored. Data redundancy can lead to problems with data consistency and integrity, as different copies of the same data may become out of sync or contain conflicting information. It can also increase the size and complexity of a database, making it more difficult to manage and maintain.