Centralised Database: The personal data is stored at a centralised location and the users from different locations can access this data. This type of database contains application procedures that help the users to access the data even from a remote location. Various kinds of authentication procedures are applied for the verification and validation of end users, likewise, a registration number is provided by the application procedures which keeps a track and record of data usage. The local area office handles this thing.
Cloud Databases: 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 optimised or built for such a virtualisation environment. There are various benefits of a cloud database, some of which are the ability to pay for membership access, 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.
Commercial Database: 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.
Distributed Database: Opposite of the centralised database concept, the distributed database has contributions from the common database as well as the information captured by local computers also. The data is not at one place and is distributed at various sites of an organisation. These sites are connected to each other with the help of communication links which helps them to access the distributed data easily. You can imagine a distributed database as a one in which various portions of a database are stored in multiple different locations(physical) along with the application procedures which are replicated and distributed among various points in a network. There are two kinds of distributed database, viz. homogeneous and heterogeneous. The databases which have same underlying hardware and run over same operating systems and application procedures are known as homogeneous databases, for eg. All physical locations in a database. Whereas, the operating systems, underlying hardware as well as application procedures can be different at various sites of a database which is known as heterogeneous databases.
End User Database: 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.
Graph Databases: 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 analysing interconnections. For example, companies might use a graph database to mine data about customers from social media.
NoSQL Database: 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 analysing large size unstructured data that may be stored at multiple virtual servers of the cloud.
Object-Oriented Databases: 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 organised 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.
Operational Database: 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.
Personal Databases: Data is collected and stored on personal computers which is small and easily manageable. The data is generally used by the same department of an organisation and is accessed by a small group of people.
SQL Relational Databases: These databases are categorised by a set of tables where data gets fit into a predefined 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 operations that can be applied over the table which makes these databases easier to extend, joining two or more databases with a common relation will modify all existing applications.