Types of Databases

This post discusses the various types of Databases available to the users and a little information about their advantages and disadvantages. In order to know the key benefits provided by the Databases read this post about Advantages of Database Management Systems. Here are the four main types of Databases-

• Hierarchical Databases
• Network Databases
• Relational Databases
• Object-Oriented Databases

Hierarchical Databases

Hierarchical Databases are the oldest types of databases around. As the name suggests, they form a hierarchy or a Parent-Child relationship. The Top level record is termed as the Parent and the subsequent lower level records are called Children. One Child can have only one Parent in case of Hierarchical databases. One of the reasons for not using Hierarchical databases is that in order to add a new node to the existing database, whole Hierarchical Tree needs to be re-defined.

Network Databases

Network Databases have similar architecture to the Hierarchical Databases. The only big difference here is that in case of Network databases, a child node may have multiple parents. So, while the Hierarchical databases form the One-to-Many relationships, Network Databases form Many-to-Many relationships.

Relational Databases

Relational Databases are totally different in terms of structure as compared to the Hierarchical and Relational databases. These types of databases use relations among the columns of the tables containing information to represent the data. These are most efficient forms of Database Management Systems available. Previous post on this blog lists the advantages provided by the Database Management Systems, most of these features are indeed part of Relational databases.

Object-Oriented Databases

The latest edition to the types of databases are the Object-Oriented databases. These types of databases use chunks of code called objects to store and manipulate data. Object oriented databases provide amazing features like ability to add Photos, Videos and other forms of multimedia information into the database. While, most of the organisations will stick to the relational databases, some may require Object oriented databases if they want more than just text stored into their databases. One of the reasons for lesser use of these types of databases is that they have very high initial costs.