Database design explains the logical structure of a certain database as well as also determines in which way data is stored, organized and manipulated.
Database design has many types and one can use one of these models depending upon their needs. Following are the most common types of Database design:
This is one of the oldest model of database which was developed for Information Management System by IBM. A tree like structure is used in this type of database model for the organization of data. We can also say that it is an organized data in a form of tree structure.
As described earlier, it is one of the oldest designs that is why it is used very rarely nowadays. Its structure includes nodes which represent records and branches which represent fields. One of the most common example of Hierarchical database is the window registry used in Windows XP.
Its advantages include that it lets very easy addition and deletion of new data or information. Data which is present at the top is very easily and quickly accessible. It works well with one to many relationships.
Some of its disadvantages is that it requires data to be stored repetitively in various sections. It only supports one to many relationships whereas many to many relationships are not supported in this type of model.
Network database is also referred as the modified or advanced version of Hierarchical database because they have structural similarities. This type of database organizes data like a graph and it can also has parent node more than one. The network model has a flexible way of representing relationships of their objects.
It is very simple and easy to design. It is more effective and efficient than hierarchical model as it represents redundancy in data more effectively. This type of model supports one to many as well as many to many relationships which is very helpful.
As this models mostly uses pointers which as a result makes the whole database design very complex. Performing structural changes to data is a very difficult process.
In 1970 E. F. Codd developed relational database. The software systems which are used to manage and maintain relational databases are known as relational database management system. This model is like a two dimensional table and data is stored in rows and column like structure. Relationship is managed by storing a common field.
Most used terms in this model are relations ( a table with rows and columns), attributes ( named columns of the relation), and domains ( set of values attributes can take).
It is the most popular type of database model. In this model, data access is not affected by changes in database structure. Revision of information is very easy to understand. Compared to other models, it is easier to maintain security.
Mapping of objects is difficult. Data integrity is also difficult in this type of model. It is not suitable for large sized databases.
In this type of database information is represented in the form of objects as used in OOP. These databases are different from table oriented relational databases. It is widely used nowadays because it is based on object oriented programming language concept.
It can handle various types of data while relational database handle only a single type of data. These various types of data include images, videos as well as text and numbers. It has low maintenance cost in comparison to other models because most of the tasks are reused and transformed into new tasks.