No SQL (Why & What & When)

This post extends from a summary of a video + e.g. + criteria. See here (cn) for detailed situatoins & examples regarding usecase. Traditional Relational DBs # Mysql, PostgreSQL, SQLite, Amazon Redshift, Amazon Aurora. Why # Too much data. Too expensive to store in one computer. Need distributed DB. However, relationship DBs (SQL) are not designed and not suitable for this situation. What # Thus, NoSQL occured, with several types. ...