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Project: Execution and Visual Representations of SQL queries in case of syntax errors


Query formulation in SQL is difficult for novices, and many errors are made in query formulation. Existing research has focused on registering error types and frequencies. Not much attention has been paid to solving these problems.

One of the problems in SQL is with the debugging process: it is not standardized and as such is typically not taught. Recent work by Gathani et al. surveyed the tools and techniques available for SQL debugging. They found that the users’ approaches to debugging, and the available tools for it, do not match at all. As a result, most users apply a trial-and-error approach.

To reduce the number of errors made, various visual systems have been developed to support SQL learners. In the Database group, we have developed SQLVis, a visual query representation for SQL. In quantative and qualitative evaluation, we have found promising results regarding query formulation progress.

One drawback in SQL is that, when syntax errors occur, most of these visual systems do not work. It is close to impossible for parsers to evaluate the query. In SQLVis, it is therefore not possible to generate a SQL representation if the user’s query contains a syntax error.

In this project you select a subset of syntax errors, find a way to amend the parsing tree in case of such errors and create a visual representation for them. Two examples include data-type related errors and aggregation-related errors.

With the creation of such error visualizations and messages, you can help learners understand and repair their errors faster, leading to better learning outcomes for our students.

Further reading:
  • Ahadi, A., Behbood, V., Vihavainen, A., Prior, J., & Lister, R. (2016). Students’ Syntactic Mistakes in Writing Seven Different Types of SQL Queries and its Application to Predicting Students’ Success. Proceedings of the 47th ACM Technical Symposium on Computing Science Education, 401–406. pdf
  • Gathani, S., Lim, P., & Battle, L. (2020). Debugging Database Queries: A Survey of Tools, Techniques, and Users. Conference on Human Factors in Computing Systems - Proceedings, 1–16. pdf
  • Odynchuk, O.R. (2022). Identifying and Visualizing Scoping Syntax Errors in SQL. MSc. Thesis. (not yet available online)
  • Taipalus, T., Siponen, M., & Vartiainen, T. (2018). Errors and complications in SQL query formulation. ACM Transactions on Computing Education (TOCE), 18(3), 1-29. pdf
Bas Witters
George Fletcher
Secondary supervisor
Daphne Miedema