Sunday, July 28, 2013

The Differences Between RDBMS and DBMS

Back to data and database, I was looking about the differences between RDBMS and DBMS and found an insight from eHow. There are several articles related, and i will share them in this blog.

Major Differences Between a Relational Database Management System & a Database Management System

A database management system (DBMS) is a computer software application that allows users to create, control, and maintain a database. A relational database management system (RDBMS) is a more complex DBMS that stores data in two-dimensional tables that are related to one another via keys. While both database applications have their uses, businesses generally prefer relational database management systems because they can handle larger sets of data.

1. Data Storage
A basic DBMS simply stores data in a persistent form, in that the data remains unaltered even if the application that created it crashes or is deleted. The data is organized into rows and columns. A database management system also maintains a set of rules so that users can access the data. A relational database management system adds a tabular structure with tables. Each table column is a field, and each table row is a record.

2. Relationships
In an RDBMS, interdependent relationships exist between sets of data. Each table has a unique field known as a key. Tables that share a key host a one-to-many, many-to-many or one-to-one relationship. There are no relationships in a DBMS, so the rows and columns are independent of one another. The benefit of maintaining relationships is referential integrity. Every time a record is changed, all related records from other tables are immediately updated.

3. Redundancy
A relational database management system is prone to less redundancy because everything is related. Therefore, duplicate sets of data cannot exist. This ensures that the data stored is accurate and relevant. A DBMS, on the other hand, allows duplicated data, which can cause data redundancy, data inconsistency and poor data integrity.

4. Additional Differences
A database management system is less secure, and it can only be used by a single user. In addition, a DBMS cannot be shared on a network or the Internet. An RDBMS can be shared online, and it supports much larger sets of data. However, a relational database management system requires more complex hardware and software, and it is much more difficult to set up.