In a "class roster" database, a teacher may teach zero or more classes, while a class is taught by one (and only one) teacher. In a "company" database, a manager manages zero or more employees, while an employee is managed by one (and only one) manager. In a "product sales" database, a customer may place many orders; while an order is placed by one particular customer. This kind of relationship is known as one-to-many.The one-to-many relationship cannot be represented in a single table. For example, in a "class roster" database, we may begin with a table called Teachers, which stores ... Read More

Relational database design (RDD) models’ information and data into a set of tables with rows and columns. Each row of a relation/table represents a record, and each column represents an attribute of data. The Structured Query Language (SQL) is used to manipulate relational databases. The design of a relational database is composed of four stages, where the data are modeled into a set of related tables. The stages are −Define relations/attributesDefine primary keysDefine relationshipsNormalizationRelational databases differ from other databases in their approach to organizing data and performing transactions. In an RDD, the data are organized into tables and all types ... 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.

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.

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.

These are the paid versions of the huge databases designed uniquely for the users who want to access the information for help. These databases are subject specific, and one cannot afford to maintain such a huge information. Access to such databases is provided through commercial links.

The end user is usually not concerned about the transaction or operations done at various levels and is only aware of the product which may be a software or an application. Therefore, this is a shared database which is specifically designed for the end user, just like different levels’ managers. Summary of whole information is collected in this database.

Data is collected and stored on personal computers which are small and easily manageable. The data is generally used by the same department of an organization and is accessed by a small group of people.