Data Independence is defined as a property of DBMS that helps you to change the Database schema at one level of a database system without requiring to change the schema at the next higher level. Data independence helps you to keep data separated from all
programs that make use of it. You can use this stored data for computing and presentation. In many systems, data independence is an essential function for components of the system. In this tutorial, you will learn:
Types of Data IndependenceIn DBMS there are two types of data independence
Levels of DatabaseBefore we learn Data Independence, a refresher on Database Levels is important. The database has 3 levels as shown in the diagram below
Consider an Example of a University Database. At the different levels this is how the implementation will look like:
Physical data independence helps you to separate conceptual levels from the internal/physical levels. It allows you to provide a logical description of the database without the need to specify physical structures. Compared to Logical Independence, it is easy to achieve physical data independence. With Physical independence, you can easily change the physical storage structures or devices with an effect on the conceptual schema. Any change done would be absorbed by the mapping between the conceptual and internal levels. Physical data independence is achieved by the presence of the internal level of the database and then the transformation from the conceptual level of the database to the internal level. Examples of changes under Physical Data IndependenceDue to Physical independence, any of the below change will not affect the conceptual layer.
Logical Data IndependenceLogical Data Independence is the ability to change the conceptual scheme without changing
Any change made will be absorbed by the mapping between external and conceptual levels. When compared to Physical Data independence, it is challenging to achieve logical data independence. Examples of changes under Logical Data IndependenceDue to Logical independence, any of the below change will not affect the external layer.
Difference between Physical and Logical Data Independence
Importance of Data Independence
Summary
What are the advantages of the database approach?A database management system helps improve organizational security, integration, compliance, and performance.. Improved data sharing and data security. ... . Effective data integration. ... . Consistent, reliable data. ... . Data that complies with privacy regulations. ... . Increased productivity. ... . Better decision-making.. Which is an advantage of the database approach quizlet?Many users can be authorized to access the same piece of information. Information is integrated so that multiple copies of the same data are not stored unless necessary. Some limited redundancy is permitted, but the DBMS is aware of the repetition. Stored data is consistent.
What is database approach in DBMS?The database approach. The database approach is an improvement on the shared file solution as the use of a database management system (DBMS) provides facilities for querying, data security and integrity, and allows simultaneous access to data by a number of different users.
Which of the following items is not the advantage of a DBMS?All of the above are true, High acquisition costs are not the advantage of a database management system. Explanation: Data redundancy has been minimized.
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