Question

Introduction to IS & IT

IT101

What problems are caused by data redundancy? Can data redundancies be completely eliminated when the database approach is used? Justify your answer in your own words.

Answer 1

Three problems are caused by data redundancy and they all, in a broad perspective, are related and involving in unnecessary storage of the same field values more than once.
* The above action will store values more than once results in the wastage of space.
* When the above action is carried out, as and when the value in any field changes, multiple occurrences or the replicas will have to be changed and updated in many records, causing overheads or simply double work, i.e., when one field's value changes any other associated fields' respective values will also need to be changed in multiple records.
* Because of the above action, whenever it is forgotten to change the values in any record, the database will have data inconsistency issues.

Yes, data redundancies can completely be eliminated when the database approach is used:
Justification for the same:
When a proper database design is used, each entity's field values are stored only once, making it unique, in a uniquely identifiable record in the entity's table.
A DataBase Management System (DBMS) reduces data redundancy and inconsistency, reducing isolated files in which any same data is repeated. DBMS controls redundancy.

DBMS uses a system in which a field's value is stored at only one place physically. However, it is requested and accessed by all applications from this place. DBMS with a Database Administrator (DBA) controls data in a DataBase in a centralized manner.