A1 Journal article (refereed)
The Effects of Database Complexity on SQL Query Formulation (2020)

Taipalus, T. (2020). The Effects of Database Complexity on SQL Query Formulation. Journal of Systems and Software, 165, Article 110576. https://doi.org/10.1016/j.jss.2020.110576

JYU authors or editors

Publication details

All authors or editors: Taipalus, Toni

Journal or series: Journal of Systems and Software

ISSN: 0164-1212

eISSN: 1873-1228

Publication year: 2020

Volume: 165

Article number: 110576

Publisher: Elsevier

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1016/j.jss.2020.110576

Publication open access: Not open

Publication channel open access:

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/68483


In Structured Query Language (SQL) education, students often execute queries against a simple exercise database. Recently, databases that are more realistic have been utilized to the effect that students find exercises more interesting and useful, as these databases more accurately mimic databases students are likely to encounter in their future work environments. However, using even the most engaging database can be counterproductive to learning, if a student is not able to formulate correct queries due to the complexity of the database schema. Scientific evidence on the effects of database complexity on student’s query formulation is limited, and with queries from 744 students against three databases of varying logical complexity, we set out to study how database complexity affects the success rates in query formulation. The success rates against a simple database were significantly higher than against a semi-complex and a complex database, which indicates that it is easier for students to write SQL queries against simpler databases. This suggests, at least in the scale of our exercise databases, that educators should also consider the negative effects of more realistic databases, even though they have been shown to increase student engagement.

Keywords: query languages; SQL; databases; complexity; education and training; learning

Free keywords: structured query language (SQL); database; database complexity; education; student learning

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2020

JUFO rating: 3

Last updated on 2022-20-09 at 13:34