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| Data Independence in DBMS |
The ability to change the scheme without having an impact on the programs and the application that needs to be rewritten is known as data independence. Programs and data are kept apart so that modifications to one do not impact the other's execution or application.
We are aware that achieving data independence is the primary goal of the three levels of data abstraction. It is crucial that updates made to one level of the database do not impact information at other levels if the database grows and changes over time. This would reduce the time and expense involved in database changes.
Based on three levels of abstraction, there are two levels of data independence. They are listed below.
Physical Data Independence
The ability to modify the internal schema without requiring modifications to the conceptual schema is known as physical data independence.
The conceptual structure of the database will remain unaffected by any modifications we make to the database system server's storage capacity.
Conceptual levels are kept apart from internal levels through physical data independence.
At the logical interface level, physical data independence takes place.
Examples Of Physical Data Independence
switching between different data structures.
utilizing modern technologies for storage, like magnetic tapes or hard drives
Transfer the database from one drive to another.
Modifying the file organization of the database
Logical Data Independence
The ability to modify the conceptual schema without requiring modifications to the external schema is known as logical data independence.
To keep the conceptual view and the external level apart, logical data independence is employed.
There would be no impact on the user view of the data if we made any changes to the conceptual view.
At the user interface level, logical data independence takes place.
The database administrator makes decisions about what data should be stored in the database and how to apply the logical level of abstraction. It offers the data's worldwide perspective. Along with the relationship, it also specifies the data that must be kept in the database.
The database's straightforward structure is provided by data independence. The functional requirement is provided by application domain entities. It offers an abstraction of the functional requirements of the system. The class object diagrams define the logical view's static structure. The database's logical structure cannot be changed by users.
Examples Of Logical Data Independence
Add, edit, or remove a new attribute, entity, or relationship without having to rewrite the existing application scripts.
To separate one record into two or more records that already exist.
Combining two tunes into a single recording.
Importance Of Data Independence
Motivates you to enhance the content's quality.
Support for database frameworks becomes reasonable.
Improvement and application of database security principles.
Application programs do not require you to alter the information structure.
Permit designers to focus on the overall architecture of the Database rather than spending endless hours worrying about how it will be used inside.
It enables you to enhance a state that is intact or cohesive.
Database fragmentation is infinitely reduced.
It is anticipated that making effective changes at the physical level will enhance the framework's display.
