The XDa-TA system for automated grading of SQL query assignments

Grading of student SQL queries is usually done by executing the query on sample datasets (which may be unable to catch many errors) and/or by manually comparing/checking a student query with the correct query (which can be tedious and error prone). In this demonstration we present the XDa-TA system which can be used by instructors and TAs for grading SQL query assignments automatically. Given one or more correct queries for an SQL assignment, the tool uses the XData system to automatically generate datasets that are designed specifically to catch common errors. The grading is then done by comparing the results of student queries with those of the correct queries against these generated datasets; instructors can optionally provide additional datasets for testing. The tool can also be used in a learning mode by students, where it can provide immediate feedback with hints explaining possible reasons for erroneous output. This tool could be of great value to instructors particularly, to instructors of MOOCs.