A NoSQL database provides a mechanism for data storage and retrieval, without using the tabular relations associated with relational databases. Originally referred to as "non-SQL" or "non-relational" databases, NoSQL databases are increasingly used in big data and real-time web application environments. NoSQL systems are also sometimes called “Not only SQL” to emphasize that they may support SQL-like query languages or sit alongside SQL databases in polyglot-persistent architectures.
A NoSQL database provides a mechanism for data storage and retrieval, without using the tabular relations associated with relational databases. Originally referred to as "non-SQL" or "non-relational" databases, NoSQL databases are increasingly used in big data and real-time web application environments. NoSQL systems are also sometimes called “Not only SQL” to emphasize that they may support SQL-like query languages or sit alongside SQL databases in polyglot-persistent architectures.
To ascertain risk, national security and intelligence professionals have long used concepts such as known knowns, known unknowns, and unknown unknowns. The idea of unknown unknowns was created in 1955 by American psychologists Joseph Luft (1916–2014) and Harrington Ingham (1916–1995). This concept continues to be used today in risk assessments and is applicable to technology. The unknown unknowns are the threats and potential problems that remain invisible until their impact manifests.