This document explores the critical aspects of data models and database technologies, emphasizing the importance of choosing the right model for specific applications. It delves into the benefits and limitations of various database systems, including relational, graph-oriented, and time series databases. The document also provides a comprehensive guide to designing and implementing a relational database system, including normalization, entity-relationship diagrams, and SQL query language. Practical examples and illustrations are used to demonstrate the concepts and techniques discussed. The document concludes with a critical evaluation of the implemented database system, addressing verification, validation, and control mechanisms.