• Database are specialized structures that allow computer-based systems to store, manage, and retrieve data very quickly.
  • data : Raw facts, or facts that have not yet been processed to reveal their meaning to the end user.
  • information: The result of processing raw data to reveal its meaning. Information consists of transformed data and facilitates decision making.
  • knowledge:  The body of information and facts about a specific subject. Knowledge implies familiarity, awareness,  and understanding of information as it applies to an environment. A key characteristic is that new knowledge can be derived from old knowledge.
  • Metadata, or data about data, through which the end-user data is integrated and managed.  The metadata describes the data characteristics and the set of relationships that links the data found within the database.
DBMS

A database management system (DBMS) is a collection of programs that manages the database structure and controls access to the data stored in the database.

Role of DBMS: The DBMS receives all application requests and translates them into the complex operations required to fulfill those requests. The DBMS hides much of the database’s internal complexity from the application programs and users.

The advantage of DBMS:

  • Improved data Sharing
  • Improved data Security
  • Better data integration
  • Minimised data inconsistency
  • Improved data access
  • Improved decision making
  • Increased end-user productivity

operational database, also known as an online transaction processing (OLTP) database, transactional database, or production database. In contrast, an analytical database focuses primarily
on storing historical data and business metrics.

Online analytical processing (OLAP) is a set of tools that work together to provide an advanced data analysis environment for retrieving, processing, and modeling data from the data warehouse.

NoSQL (Not only SQL) is generally used to describe a new generation of database management systems that is not based on the traditional relational database model.
NoSQL databases are designed to handle the unprecedented volume of data, variety of data types and structures, and velocity of data operations.