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Database code fragments exist in software systems by using Structured Query Language (SQL) as the standard language for relational databases. Traditionally, developers bind databases as backends to software systems for supporting user applications. However, these bindings are low‐level code and implemented to persist user data, so Object Relational Mapping (ORM) frameworks take place to abstract database access details. Both approaches are prone to problematic database code fragments that negatively impact the quality of software systems. We survey problematic database code fragments in the literature and examine antipatterns that occur in low‐level database access code using SQL and high‐level counterparts ORM frameworks. We also study problematic database code fragments in different and popular software architectures such as Service‐Oriented Architecture, Microservice Architecture, and Model View Controller. We create a novel categorization of both SQL schema and query antipatterns in terms of performance, maintainability, portability, and data integrity.

Road maps are important in our personal lives and are widely used in many different applications. Therefore, an up-to-date road map is essential. The huge amount of GPS data collected from moving objects provides an opportunity to generate an up-to-date road map. In this paper, we propose a novel method to generate road maps using GPS trajectories that is accurate with good coverage area, has a minimum number of vertices and edges, and several details of the road network. Our algorithm starts by identifying the locations of intersections using a line simplification algorithm with spatial-constraints and grid-based method. Then, it creates graph connectivity information to connect intersections and build road segments. In addition, our algorithm extracts road features such as turn restrictions, average speed, road length, road type, and the number of cars traveling in a specific portion of the road. To demonstrate the accuracy of our proposed algorithm, we conduct experiments using two real data sets and compare our results with two baseline methods. The comparisons indicate that our algorithm is able to achieve higher F-score in terms of accuracy and generates a detailed road map that is not overly complex.