A collected information which is in an organized form for easier access, management, and various updating is known as a database.Before going into a further discussion of databases, we must have a prior knowledge of exactly what is a DATA? Data can be defined as a collection of facts and records on which we can apply reasoning or can-do discussion or some calculation. The data is always easily available and is in plenty. It can be used for processing some useful information from it. Also, it can be in redundant, can be irrelevant. Data can exist in form of graphics, ... Read More

The network model is the extension of the hierarchical structure because it allows many-to-many relationships to be managed in a tree-like structure that allows multiple parents.There are two fundamental concepts of a network model −Records contain fields which need hierarchical organization.Sets are used to define one-to-many relationships between records that contain one owner, many members.A record may act as an owner in any number of sets, and a member in any number of sets.P.S. Set must not be confused with the mathematical set.A set is designed with the help of circular linked lists where one record type, the owner of ... Read More

The relational data model was introduced by C. F. Codd in 1970. Currently, it is the most widely used data model. The relational data model describes the world as “a collection of inter-related relations (or tables).” A relational data model involves the use of data tables that collect groups of elements into relations. These models work based on the idea that each table setup will include a primary key or identifier. Other tables use that identifier to provide "relational" data links and results. Today, there are many commercial Relational Database Management System (RDBMS), such as Oracle, IBM DB2, and Microsoft SQL ... Read More

A database model determines the logical structure of a database and determines in which manner data can be stored, organized and manipulated on a fundamental basis. before the databases are designed, the only way to store data was are in file storage, which increases the complexity as programmers had to go to great lengths to extract the data, and their programs had to perform complex parsing and relating.There are various languages like Perl process the text in an easier manner due to its powerful regular expressions. However, accessing the data from files is still a complex task. There is no ... Read More

The graph is a collection of nodes and edges where each node is used to represent an entity and each edge describes the relationship between entities. A graph-oriented database, or graph database, is a type of NoSQL database that uses graph theory to store, map and query relationships.Graph databases are basically used for analyzing interconnections. For example, companies might use a graph database to mine data about customers from social media.

An object-oriented database is a collection of object-oriented programming and relational database. There are various items which are created using object-oriented programming languages like C++, Java which can be stored in relational databases, but object-oriented databases are well-suited for those items.An object-oriented database is organized around objects rather than actions, and data rather than logic. For example, a multimedia record in a relational database can be a definable data object, as opposed to an alphanumeric value.

Now a day, data has been specifically getting stored over clouds also known as a virtual environment, either in a hybrid cloud, public or private cloud. A cloud database is a database that has been optimized or built for such a virtualized environment. There are various benefits of a cloud database, some of which are the ability to pay for storage capacity and bandwidth on a per-user basis, and they provide scalability on demand, along with high availability.A cloud database also gives enterprises the opportunity to support business applications in a software-as-a-service deployment.

These databases are categorized by a set of tables where data gets fit into a pre-defined category. The table consists of rows and columns where the column has an entry for data for a specific category and rows contains instance for that data defined according to the category. The Structured Query Language (SQL) is the standard user and application program interface for a relational database.There are various simple operations that can be applied over the table which makes these databases easier to extend, join two databases with a common relation and modify all existing applications.

Information related to operations of an enterprise is stored inside this database. Functional lines like marketing, employee relations, customer service etc. require such kind of databases.

These are used for large sets of distributed data. There are some big data performance issues which are effectively handled by relational databases, such kind of issues are easily managed by NoSQL databases. There are very efficient in analyzing large size unstructured data that may be stored at multiple virtual servers of the cloud.